He raised the flag might be better English.

The English translation is not grammatical: He rose the flag. Rose is the past participle of to rise, which is an intransitive verb. The correct verb is the transitive verb to raise and takes an object (eg, "the flag").

So, one could say "He raised the flag", or "The flag rose".

See: http://m.wikihow.com/Know-the-Difference-Between-Rise-and-Raise