Short answers, pulled from the story.
Richard Burbage almost certainly played Othello in the first recorded performance on the 1st of November 1604 at Whitehall Palace. The play is believed to have been written between 1601 and 1604.
There is no final scholarly consensus. E. A. J. Honigmann, editor of the Arden Shakespeare edition, concluded the ethnic background is ambiguous, as the term "Moor" was used in the Renaissance to cover a wide range of dark-skinned people from North Africa to Sub-Saharan Africa. Critics including Virginia Mason Vaughan argue the Sub-Saharan reading fits more clearly, while the earliest known North African interpretation did not appear until Edmund Kean's 1814 production.
Margaret Webster's 1943 staging was the first American production to feature a black actor as Othello alongside an otherwise all-white cast. It ran for 296 performances, nearly twice as long as any other Shakespearean play on Broadway, and became the first nearly complete recording of a Shakespeare play released on records.
The 1965 film version of Olivier's Royal National Theatre production holds the record for the most Oscar nominations for acting ever given to a Shakespeare film. Olivier, Frank Finlay, Maggie Smith, and Joyce Redman were all nominated for Academy Awards.
Abd el-Ouahed ben Messaoud ben Mohammed Anoun was the ambassador of the King of Morocco to Queen Elizabeth I. He stayed in London in 1600 with his retinue for several months and prompted widespread public discussion. Some scholars suggest he may have inspired Shakespeare's Othello, written only a few years later, though E. A. J. Honigmann questions this connection.
Patrick Stewart played Othello in a "photo negative" production at the Shakespeare Theatre Company in Washington, D.C. in 1997, directed by Jude Kelly. Stewart, a white actor, played Othello opposite an otherwise all-black cast, inverting the play so Othello became a comment on a white man entering a black society.