Scroll down to the 6th paragraph to find out what happened to the man Port Harcourt is named after. Thanks JB for the link.
The Wikipedia entry for him also provides further evidence:
'Harcourt was known as a sexual predator attracted to both sexes. He tried to rape Dorothy Brett, the daughter of Lord Esher, and followed this by an attempt to seduce his son. Dorothy Brett wrote of him that "it is so tiresome that Loulou is such an old roué. He is as bad with boys as with girls .. he is simply a sex maniac. It isn't that he is in love. It is just ungovernable Sex desire for both sexes". His behaviour was known and tolerated in private, but when he attempted to seduce one 12-year-old boy (Edward James, who grew up to become a great collector of surrealist and other contemporary art), the boy's mother began to tell the whole of society. Harcourt could not tolerate the impending disgrace and he committed suicide at his London home in Brook Street.'
How PH got its name is almost as casual a story as how Nigeria got its name (from Flora Shaw):
'In August 1913, the Governor–General of Nigeria, Sir Frederick Lugard wrote to Harcourt, then Secretary of State for the Colonies, "in the absence of any convenient local name, I would respectfully ask your permission to call this Port Harcourt." To this the Secretary of State replied, "It gives me pleasure to accede to your suggestion that my name should be associated with the new Port."'
Addendum (26th August). More on Loulou Harcourt's activities here (scroll down to the paragraph that begins "Historians generally doubt.."