The 1900 International Congress of Mathematicians was the second International Congress of Mathematicians held in Paris from August 6 to August 12, 1900.

The Congress brought together 250 full members.

Congress course 
The first meeting took place at Café Voltaire, on August 5, at 8:30 p.m. before the official inauguration of the Congress, and allowed several of its members to make contacts, to bond or to renew friendships.

The delegates met on August 7 for a lunch, served at the École Normale Supérieure whose Director, Georges Perrot, had kindly provided us with the Salle des Actes; Jules Tannery graciously agreed to do the honors. Perrot, Moritz Cantor and Darboux spoke successively with much applauded toasts.

The delegates were received on August 10 by the President of the French Republic, Émile Loubet, and on August 11, along with their colleagues from the Physics Congress, by Prince Roland Bonaparte, whose generous dedication to scientific enterprises is known.

Finally, after the close of the Congress, its members gathered in large numbers on August 12, at noon, for a farewell banquet that many ladies and young girls were kind enough to honor and charm with their presence. The President of the Congress unfortunately found himself too tired to participate. Many toasts were raised, first by Darboux, who excused Henri Poincaré, then by Carl Friedrich Geiser, on behalf of the foreign delegates, by Jules Tannery who proposed the health of those absent, and by Cyparissos Stephanos and Nikolái Vasíliev; Darboux, finally, spoke again in his own name, and improvised a charming speech, in which he underlined how close it is that mathematicians must feel, since there are no scientists whose work is more disinterested, nor less likely to conquer the masses of the laity.

Some members of the Congress met in the evening at the Opera, during a gala evening for which the Minister of Public Instruction and Fine Arts, Georges Leygues, reserved a few places for members of the Congress of the International Congress of Mathematicians.

Hilbert's Problems 
In many ways, it was David Hilbert's lecture on Hilbert's Problems in Mathematics the most famous lecture given at an International Congress of Mathematicians. It is sometimes described as a plenary conference and sometimes not. This is because Hilbert was invited to give a plenary lecture at the 1900 Congress. He couldn't decide on a topic and discussed what he should talk about with Hermann Minkowski and Adolf Hurwitz. Eventually he decided to discuss some outstanding math problems, but took a long time to write his lecture. The 1900 Congress program was released before it was ready, so his speech was not advertised as a plenary conference. It was delivered in Congress during a joint session of the Education Section and the History Section (due to lack of time Hilbert only spoke about 10 of his 23 issues in the conference, although all 23 problems appear in the published). It was on August 8, at 9:00 a.m. when David Hilbert gave his conference. It was titled On Future Problems in Mathematics.

By the time the Conference Proceedings appeared, the organizers decided that, because of its importance, they would put Hilbert's article in the section with plenary lectures. Another point worth noting is that  Most of this congress was in French, but there was a discussion of math problems published in so many languages.

Right after Hilbert's exposition, Giuseppe Peano said that Alessandro Padoa's subsequent communication would address Hilbert's issue no. 2. Rudolf Mehmke recalls that he proposed certain monographic representations in space from which a solution of the general equation of the seventh degree could result.

References 

1900
Paris