Niall Ferguson, who is a professor of history at Harvard, immediately comes to mind. He wrote a book called Empire a decade or so ago, which is a history of the British Empire, butis also aimed toward rehabilitating the reputation of both the British Empire and the concept of Empire more generally.

As you may imagine, Fergusson is a fairly controversial figure. There are a dozen different reasons other professional historians don't like him. One of the huge ones is obviously that he puts out contrarian arguments. Another is that he aims his books toward a popular audience. Sometimes historians are snobs.

Keith Windschuttle is one such historian. He is a conservative Australian historian who disputes that the English committed genocide against the Aboriginals when they settled/invade/colonised Australia (depending on how you classify the events). He sees Aboriginal rights, including land rights and the need for reparations for past abuses of Aboriginal people as a left-wing 'cause' and thinks that historians distort the historical record to support that cause.

Windschuttle wrote an article in 2002 titled 'In Defense of Colonialism', which argues that western colonialism made the world a better place. Like Ferguson, he is a very controversial historian. While I've not read enough of his work to know if he defends it wholeheartedly, I'd say he definitely defends it, to the point of denying actual evidence.