Chekhov was born on 29 January 1860, in Taganrog, southern Russia, where his father ran a grocery store and was director of a choir for Orthodox Christians. Chekhov attended a school for Greek boys, and continued there even after his father and mother moved, in 1876, to Moscow (where Chekhov’s older brothers were at university) to avoid being prosecuted locally for unpaid debts. Chekhov then covered the cost of his own schooling by tutoring, catching and selling goldfinches, and selling short sketches to newspapers. Only in 1879, having gained admission to the medical school at Moscow University, did he rejoin his family.
Chekhov began contributing to humorous magazines in Moscow to help supplement his family’s income, but soon graduated to short stories and more serious literary publications. By 1884, he had qualified as a physician; but he had also contracted TB, which was to blight the rest of his life. In 1887, with guidance from one of the most celebrated Russian writers of the time, Dmitry Grigorovich, Chekhov’s story collection At Dusk won the coveted literary Pushkin Prize. The same year, he turned his pen to plays with Ivanov, which proved a critical success. His four most famous plays - The Seagull, Uncle Vanya, Three Sisters and The Cherry Orchard - were not written, however, until the last decade of his life, starting in 1896. As is well known, Chekhov almost gave up writing plays when The Seagull was panned (the audience booed on its first night).
In 1892, Chekhov bought an estate, Melikhovo, about 40 miles south of Moscow, where he lived - enjoying his landlord responsibilities - until ill health obliged him, in 1897, to move further south to Yalta, with its warmer climate. In 1902, he married the actress Olga Knipper, but two years later, in 1904, TB finally got the better of him. Wikipedia has a good online biography, but try also TheatreHistory.com or Andreas Andreas’s site hosted by Brandeis University for more information.
Chekhov was not a diarist, but he did keep notebooks in which he jotted down his literary thoughts, ideas, themes and sketches for work. A collection of these were translated into English by S. S. Koteliansky and Leonard Woolf and published by B. W. Huebsch, New York, in 1921. In fact, the first section of the book - Note-Book of Anton Chekhov - is a collection of diary entries written by Chekhov over several years, all very short and quite intermittent. The full text is freely available at Internet Archive, but the text of the diary section is also easily accessible at Wikisource. Here are a few entries from the start of the diary section.
September
‘2 September in Novorissisk. Steamer Alexander 11. On the 3rd I arrived at Feodossia and stopped with Souvorin. I saw I. K. Aivasovsky [famous painter] who said to me: ‘You no longer come to see me, an old man.’ In his opinion I ought to have paid him a visit. On the 16th in Kharkov, I was in the theatre at the performance of ‘The Dangers of Intelligence’. 17th at home: wonderful weather.
Vladimir Sloviov [famous philosopher] told me that he always carried an oak-gall in his trouser pocket, - in his opinion, it is a radical cure for piles.’
17 October 1896
‘Performance of my Seagull at the Alexandrinsky Theatre. It was not a success.’
29 October 1896
‘I was at a meeting of the Zemstvo Council at Sezpukhovo.’
10 November 1896
‘I had a letter from A. F. Koni who says he liked my Seagull very much.’
26 November 1896
‘A fire broke out in our house. Count S. I. Shakhovsky helped to put it out. When it was over, Sh related that once, when a fire broke out in his house at night, he lifted a tank of water weighing four and half cwt and poured the water on the flames.’
4 December 1896
‘For the performance [of The Seagull] on the 17th October see Theatral, No 95, page 75. It is true that I fled from the theatre, but only when the play was over. In L’s dressing room during two or three acts. During the intervals there came to her officials of the State Theatres in uniform, wearing their orders, P_ with a Star; a handsome young official of the Department of the State Police also came to her. If a man takes up work which is alien to him, art for instance, then, since it is impossible for him to become an artist, he becomes an official. What a lot of people thus play the parasite round science, the theatre, the painting, - by putting on a uniform! Likewise the man to whom life is alien, who is incapable of living, nothing else remains for him, but to become an official. The fat actresses, who were in the dressing- room, made themselves pleasant to the officials - respectfully and flatteringly. (L expressed her delight that P, so young, had already got the Star.) They were old, respectable house-keepers, serf-women, whom the masters honored with their presence.’
21 December 1896
‘Levitan suffers from dilation of the aorta. He carries clay on his chest. He has superb studies for pictures, and a passionate thirst for life.’
31 December 1896
‘P. L. Seryogin, the landscape painter, came.’