| 1823 | | British explorers Walter Oudney, Hugh Clapperton and Dixon Denham visit Lake Chad (which they name Lake Waterloo) during an expedition from Tripoli to Bornu. |
| 1850 | | James Richardson, German naturalist Heinrich Barth and geologist Adolf Overweg depart Tripoli accompanied by a retinue of guides and servants bound for Lake Chad. Their supplies include a large wooden boat, carried in two sections, in which they intend to explore the lake. |
| May | Richardson, Barth and Overweg part company agreeing to make their way to Lake Chad separately and agreeing to meet at Kukawa in April 1851. |
| 1851 | April | James Richardson dies of fever three weeks before Barth arrives at Kukawa. |
| May | Adolf Overweg arrives at Lake Chad exhausted and suffering from fever. Heinrich Barth explores the territory south and east of the lake while Overweg recovers sufficiently to explore the lake itself in the boat they had brought across the Sahara . The two men stay in the Lake Chad region for about 15 months before Overweg dies of malaria at the age of 29. |
| 1852 | November | Heinrich Barth leaves Lake Chad bound for Timbuktu. |
| 1854 | | Heinrich Barth leaves Timbuktu and begins working his way back to Lake Chad. On the way he learns that a rescue party led by Edward Vogel, sent out by the British government had already arrived at the lake. After meeting with Vogel at Lake Chad, Barth decides to go on to Kukawa while Vogel decides to head for Zinder, a town almost 300 miles west of Lake Chad where he would rejoin Barth before starting the journey north across the desert. |
| 1855 | September | Heinrich Barth reaches London by way of Tripoli having made the desert crossing without Vogel, who decided to stay in Africa and explore the Lower Niger. Vogel was murdered in 1856 on his way back to the Nile. |
| 1856 | | The Royal Geographical Society’s Patron's Medal is presented to Heinrich Barth, "for his extensive explorations in Central Africa, his excursions about Lake Chad and his perilous journey to Timbuctu". |
| 1870 | | Lake Chad rises to a near record height but will shrink severely in the decades of drought. |
| | German doctor Gustav Nachtigal investigates the hydrography of Lake Chad in detail and explores the Tibesti. |
| 1879 | July | Sudanese slave trader Rabah, son of Zobeir Rabah, conqueror of Bornu, is defeat by Egyptian forces under Romolo Gessi Pasha and flees westward with 700 Bazingir warriors. Rabah gathers an army of 35,000 men, makes himself master of Kreich and Dar Banda, southwest of Wadai and gains control of trade in Eastern Chad. |
| 1882 | | The Royal Geographical Society’s Founder's Medal is presented to Doctor Gustav Nachtigal, "for his journeys through the Eastern Sahara". |
| 1890 | | The Lake Chad region is divided into French, German and British Zones. |
| 1891 | | French explorer Paul Crampel is killed in Dar Banda by a chieftain loyal to Rabah. Crampel's stores, including 300 rifles, are sent to Rabah who begins to march on Wadai. The Wadai fend off the invasion and Rabah turns west and establishes himself in Bagirmi, a state south-east of Lake Chad. |
| 1893 | | Rabah overthrows the Sultan of Bornu. |
| November 15 | An Anglo-German agreement specifies Lake Chad as the northern starting point of the border between Nigeria and Cameroon. |
| 1897 | | Rabah’s invasion of Nigeria is turned back by British forces under Sir George Goldie of the Fula at Bida and forced to return to Bornu. |
| | A French Expedition under Emile Gentil reaches Lake Chad by steamer via the Congo, Shari and Bagirmi Rivers. Gentil installs a French resident to advise the Sultan of Bagirmi but soon after Gentil’s departure, Rabah attacks Bagirmi once again forcing the Sultan and the Resident to flee. |
| 1898 | May | Minister of Colonies Andre Lebon implements a policy aimed at establishing French control in the heart of Africa and linking the colonies of north and west Africa. Lebon dispatches an expedition under Marine Infantry Captain Paul Voulet and Captain Julien Chanoine on a mission to, “visit the countries between the French Sudan and Lake Chad ... and enter into relations with the leaders of the principle countries of the central Sudan.” Other French missions are dispatched to Lake Chad under Emile Gentil from the Ubangi and under Fernand Foureau and Commandant Lamy across the Sahara from Algeria. The combined missions are further ordered to bring Rabah under control and end the slave trade by negotiation or force of arms. |
| September 21 | The Voulet–Chanoine Mission departs Bamako on the Niger for Lake Chad with 8 NCOs, 50 regular riflemen, 20 spahis, 200 auxiliary riflemen, 700 porters and over 25 tons of equipment. |
| 1899 | March 21 | An Anglo-French accord divides the Sahara into two spheres of influence along a line running southeastward from the intersection of 16° east longitude and the Tropic of Cancer to its intersection with 24° east longitude. |
| Summer | Rabah attacks and routs the advance post of French expedition sent to recapture the country. Lieutenant Bretonnet, the French commander is killed. |
| September 4 | Lieutenant Joalland reaches Lake Chad with a remnant of the ill-fated Voulet-Chanoine Mission which degenerated into murder, mutiny and pillage as it made its way up the Niger. |
| October | French troops under Captain Robillot defeat Rabah, who retreats towards Wadai. |
| 1900 | April 22 | Rabah is killed in a battle with the French at Kousseri. The chieftain's head is cut off and taken to the French camp. Major Lamy, the French commander, is mortally wounded in the fighting. |
| May | French Commissioner Emile Gentil establishes Fort Lamy (present day N'djamena). |
| September 5 | A decree establishes the Military Territory of the Lands and Protectorates of Chad within the Ubangi-Shari colony. |
| 1901 | | The French come under attack from Fader Allah, Rabah’s son who fled to Nigeria with 2,500 riflemen after the Battle of Kousseri. French troops under Captain Dangeville defeat the forces of Fader Allah in a pitched battle at Gujba, Nigeria. Fader Allah is mortally wounded in the fighting. 1902 |
| May 2 | A German military expedition reaches the shores of Lake Chad for the first time. |
| July | The Italian Government accepts the border between Chad and Libya derived from the 1899 Anglo-French accord delimiting spheres of influence in the Sahara. |
| 1902 - 1903 | French officers under Colonel Destenave make detailed surveys of the southeastern and eastern shores of Lake Chad and the adjacent islands. |
| 1903 | | French Captain E. Lenfant reaches Lake Chad via the Benue, circumnavigates the lake and proves the existence of a waterway linking the Shari and the Niger. |
| | The islands along the shore of Lake Chad in the Kanem region sighted by Overweg in 1851 now form part of the mainland and desiccation has led to formation of new ones lying 5 to 20 meters from the shore. |
| December 29 | Under a decree effective July 1, 1904 The French Congo is divided into the Gabon Colony, the Middle Congo Colony and Ubangi-Shari-Chad Colony which was further divided into the Ubangi-Shari and the Chad Circumscriptions. |
| 1904 | | An Anglo-German expedition led by Major Glauning surveys the border with Nigeria between Yola and Lake Chad. The Niger-Benue-Lake Chad expedition under Fritz Bauer is active in the same region. |
| 1905 | | A British party led by Lieutenant Boyd Alexander explores the Lake Chad region during an expedition for which Alexander is later awarded the Royal Geographical Society’s Founder’s Medal, “for his three years’ journey across Africa from the Niger to the Nile". Alexander found that a half century of drought had left towns which were once on the shores of Lake Chad over 20 miles from it. |
| 1908 | April | France and Germany sign a convention which cedes the “Duck’s Beak” region of Bongor to France in exchange for other territories from Gabon, Ubangui and Chad. |
| 1909 | | French troops crush resistance in the Wadai region. The remaining northern regions; Borkou, Ennedi and Tibesti remain under French military administration until 1965. The southern populations, long the target of Arab slave traders, are more favorably disposed towards the French presence. |
| 1910 | January 15 | The French Congo is renamed French Equatorial Africa. The French colonial administration favors development of the fertile South where a cotton economy develops. Southern Chad becomes a source of forced labor for construction of the Congo-Ocean Railway. |
| 1914 | April | France and Great Britain sign an accord on demarcation of the border between Chad and Anglo-Egyptian Sudan. |
| 1917 | January 25 | French forces are accused of massacring 400 Moslem clerics in the Wadai region. |
| 1919 | | Fort Lamy is incorporated as a municipality. |
| 1920 | August 10 | The Military Territory of Chad is transformed into civil colony with the capital at Fort Lamy. |
| 1923 | | A precise ground survey demarcates the border between Chad and the Sudan. |
| 1924 | | The border between Chad and the Sudan is demarcated on the basis of a 1919 Anglo-French accord. |
| 1927 | | At the end of the Italo-Sennousi War, Italian authorities in Libya lay claim to Chadian territories south of the border agreed to in a 1902 exchange of notes with the French Government. The Italian claim is based on succession to the Ottoman Vilayat of Tripoli which had administered the area before the Italian colonization of Libya. |
| 1929 | | The Tibesti region is integrated within the colony of Chad. |
| June 29 | Italy lays claim to all Chadian territory north of the 18th parallel in a note to the French Government which rejects the Italian demand. |
| 1935 | | The French Government agrees to cede the Aozou Strip, a strip of land 120 miles wide running parallel to the existing frontier between Chad and Libya, to Italy in an effort to satisfy Italian demands regarding the status of Italian nationals in Tunisia as well as irredentist claims on Nice. The treaty is ratified by the parliaments of both countries but never comes into force owing to the establishment of the Rome-Berlin axis. |
| 1940 | July 16 | Governor Félix Éboué informs General de Gaulle that he will support Free France. Éboué, born in French Guiana of mixed African and European parentage, is disgusted by Marshal Petain’s capitulation to the Nazi philosophy. |
| August 26 | Chad becomes the first French colony to support General de Gaulle. Governor Félix Éboué and Colonel Pierre Marchand, Commandant of the Régiment de Tirailleurs Sénégalais du Tchad, publicly proclaim Chad’s rally to Free France. |
| October 13 | General de Gaulle meets with General Catroux in Fort Lamy. Catroux has been ordered to Cairo to assist in planning a move against Vichy forces in Lebanon and Syria. De Gaulle suspects the British of plotting to place Catroux, who out ranks him by three stars, at the head of the Free French movement. De Gaulle leaves the meeting satisfied with Catroux’s loyalty but remains suspicious of British aims in the Middle East for the duration of the war. |
| October | Combat Group No.2, the Topic Squadron of the Free French Air Force, composed of six planes under the command of Captain Jean Astier de Villatte is dispatched to Chad with orders to defend the colony against the threat of an Italian offensive coming from Libya or a Vichy offensive launched from Niger. |
| December 3 | Colonel Jacques Leclerc is appointed commander of the Régiment de Tirailleurs Sénégalais du Tchad and military commandant of Chad. General de Gaulle entrusts the mission of opening a French front against the Italians in Libya to Leclerc, his adjudants Lieutenant Colonel d’Ornano and Captain Jacques Massu, and their 6,000 man force which includes 500 Europeans. |
| December | Free French Air Force Combat Groups No. 1 and 2 are merged under the command of Captain Astier de Villatte to form the Reserve Bombardment Group No. 1 which is composed of two squadrons of six Blenheim bombers. One squadron is stationed at Maiduguri near Fort Lamy. |
| 1941 | January 11 | A Free French column under Lieutenant Colonel Jean Colonna d’Ornano, commander of the Borkou - Ennedi region in northern Chad, raids the Italian base at Mourzouk, Libya. The Italian airfield in neutralized but Lieutenant Colonel d’Ornano is killed. |
| January 27 | Leclerc departs Faya Largeau to prepare an attack on the Italians at Koufra Oasis in Libya. |
| January | Free French Air Force Reserve Bombardment Group No. 1 begins flying aerial photo reconnaissance missions over of the Italian base at Koufra. |
| February 10 | Leclerc returns to Faya Largeau, after a reconnaissance mission to Koufra, Libya. |
| February 17 | The Leclerc Column takes its first step in a march from Chad to the Rhine in departing Faya Largeau to attack the Italians at Koufra Oasis. |
| March 1 | The Leclerc Column seizes the Oasis of Koufra in Libya from the Italians with support from the Free French Air Force formation that later becomes the Bretagne Squadron. Leclerc addresses his troops following the Italian surrender, "We are on the march. We will not stop until the French flag flies over the Cathedral of Strasbourg." The declaration goes down in posterity as the Oath of Koufra. |
| March 3 | General de Gaulle wires Leclerc, “You have proven to the enemy that he is not finished with the French Army. The glorious troops of Chad and their chief are on the route to victory." |
| August 11 | Félix Eboué is appointed Governor General of French Equatorial Africa. |
| 1942 | January 1 | The Bretagne Group of the Free French Air Force comprised of the Nantes and Rennes Squadrons is formed in Chad to provide air support for Colonel Leclerc’s offensive against the Italians in Fezzan. |
| March 25 | General Leclerc is named Commander in Chief of Free French forces in Africa. General de Gaulle appoints Colonel François Ingold to lead the troops of Chad. |
| December | The Leclerc Column is rechristened Force L and reinforced with elements of the African Free Corps, the Army of Africa and escapees from France by way of Spain. |
| 1943 | January 25 | The first French troops coming from Chad enter Tripoli following a march of over 3,000 kilometers. General Leclerc arrives in the evening. |
| January 26 | General Leclerc meets with General Montgomery, commander in chief of the British 8th Army. |
| January 27 | General Leclerc greets Commandant Bouillon of the Marine Infantry Battalion of the Pacific at the Tripoli airport in the first junction of the Free French from Chad with the Free French arriving from the Middle East. |
| June | The Régiment de Tirailleurs Sénégalais du Tchad, now based at Sabratha in Tripolitania, becomes part of the Free French 2nd Division and is renamed the Régiment de Marche du Tchad. |
| 1944 | August 1 | The Régiment de Tirailleurs Sénégalais du Tchad lands at Utah Beach in Normandy. |
| August 24 | The 9th Company of the 3rd Battalion of the Régiment de Marche du Tchad under Captain Raymond Dronne becomes the first Allied unit to reenter Paris. |
| August 25 | Elements of the Régiment de Marche du Tchad seize the German command posts in Paris at the Hotels Majestic and Meurice. |
| 1945 | May 5 | The Régiment de Marche du Tchad captures Hitler's Berghof at Berchtesgaden. |
| October | Native Chadians are represented by their Grand Electors in the Constituent Assembly. |
| 1946 | October 27 | Chad becomes a French Overseas Territory under the Constitution of the Fourth Republic. |
| November | Gabriel Lisette, a colonial administrator born in the French West Indies, is elected as Chad’s deputy in the French National Assembly. |
| 1947 | February | Gabriel Lisette and Chadian teacher François Tombalbaye found the Chadian Progressive Party (PPT), affiliated with the African Democratic Rally of Félix Houphouët-Boigny, is established in the south. |
| 1952 | April 16 | The French colonial army massacres demonstrators at Bebalem (Logone Orientale). |
| 1957 | March | The Chadian Progressive Party wins the elections for the territorial assembly created under the Defferre Law. Three parties contest the first Chadian elections held under universal suffrage. |
| 1958 | November 28 | A referendum on the Constitution of the Fifth Republic is approved by 98% of Chadian voters. Chad becomes an autonomous republic within the French Community. |
| 1959 | May 31 | The Chadian Progressive Party (PPT RDA) wins 57 of 85 seats at stake in legislative elections. |
| June 16 | Premier François Tombalbaye forms the first government of the Republic of Chad. |
| 1960 | August 11 | Chadian independence is proclaimed in the presence of André Malraux, representative of French President Charles de Gaulle. François Tombalbaye becomes president after banishing Gabriel Lisette to exile and establishes a dictatorship. |
