He works for the Ministry of Magic[?], in the Muggle Artifacts department. He is obsessed with learning about muggle customs and inventions. For this and perhaps other reasons, his career advancement appears to be at a standstill. He has been a consistent opponent of Lord Voldemort.
His younger son Ron is one of Harry Potter's best friends. Harry and his other best friend Hermione Granger enjoy spending time with the Weasley family and they seem to have been accepted as unofficial members of it.
Wikipedia contains spoilers In Harry Potter and Order of the Phoenix[?], Mr. Weasley is a member of the Order of the Phoenix and is attacked by a snake being controlled by Voldermort. Harry who is mentally connected with Voldermort, manages to see this in this dream and is able to warn the Hogwarts authorities and Mr. Weasley was saved just in time and sent to St. Mungo's Hospital for Magical Maladies and Injuries[?]
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wikipedia.org dumped 2003-03-17 with terodump