Reigned for either 11 or 15 years depending on interpretation of dates, 1294 BC – 1279 BC or 1290 BC to 1279 BC. The temple was completed by his son and successor Rameses II.
http://egyptsites.wordpress.com/2009/02/09/temple-of-seti-i/http://en.wikipedia.org/wiki/Seti_I
