Analysis of information sources in references of the Wikipedia article "Trondheim" in Simple English language version.
During the spring of 1179, Magnus arrived with his army. The two armies met on June 19 in the Battle of Kalvskinnet (Slaget på Kalvskinnet) with the result being a clear victory for Sverre, securing his grip on Trøndelag. Magnus Erlingsson again attacked Trøndelag in the spring of 1180.
It was founded in 997 by King Olaf I Tryggvason as the village of Kaupangr; he built a church and a royal residence, Kongsgård, there.
Most historians accept that Olav Tryggvason founded Trondheim in the year 997.