In Jom's red hot list of 27 Tory "indiscretions" three were instances attributed to Boris Johnson:

1: The sarcastic comment about the Queen, the Commonwealth and the Piccaninnies - Which if actually studied proves to be correct, acceptable and accurate use of language for describing any Royal Visit to quite large sections of the Commonwealth.

2: The comment in an article about the low IQ of "Black Africans" which Jom's link said Boris Johnson wrote - Investigation shows that Boris Johnson wrote no such article, it did appear in the "Spectator" while Boris Johnson was Editor, the article itself was written by Taki Theodoracopulos.

3: Then there was the "racist" Barack Obama comments - which of course were nothing of the sort, certainly not as far as Barack Obama himself was concerned.

Oh and before you ask. Why did he apologise? It is the sort of thing anyone conversant with what constitutes good manners and behaviour does when told that offence has been taken at something said inadvertently.