What nationality was Sir William Herschel?

The great astronomer, Sir Wilhelm(William) Herschel (15 November 1738 -- 25 August 1822) was originally German being born in the city of Hanover. He emigrated to Britain when he was 19 and became a British citizen. Therefore, his nationality is British.

I saw the comment of the supervisor of WIKI.ANSWERS.COM and I share his opinion.

And I also agree withn the present author (with improvement and addition).

added more:

Wilhelm...was German (born German), from historical facts 'no doubt'.

But Later Wilhelm became William by his own will and agreed to be British.

He lived in Britain till the day he last breathed.

And he was honored 'SIR" because he was been accepted as Brit.