Historians would have liked to have known much more about the life of this somewhat mythical character, a man who many genealogists can trace their family back to. Some believe that he was born a decade or two before 1500, and that he was at least 125 years old!
One certain fact is that Adrian was Dutch, and that he initially came to Bergen as a crewman on a merchant ship. Later he settled there, and married a widow. Whether he was an accomplished falconer (training falcons for hunting, in Norwegian his last name suggests this) is quite unclear. What is known about his life is his connection to trade and shipping.
During the 1540s (if not before) he arrived in Trondheim and stayed in the city for the rest of his long life. For the second time he married a widow, and some sources suggest that he had 18 sons and six daughters!
Over time it became common that merchants from abroad acquired central positions in Trondheim. In this respect Adrian was one of the pioneers. The position of mayor was fairly new. While it is not certain that it was a lucrative station, it must undoubtedly have given him influence. Adrian was the mayor of Trondheim from around 1547, first together with Nils Lauritzen, and later with Peder Bartskjær and Peder Småsvenn. In addition to this he was an export and import trader, using his own ships.
He lived in Ila, where Arilds gate [street] is today. Earlier the country retreat Arildsløkken was situated there, and this name is said to be a derivation of Adrians løkke [meadow].
Towards the end of his life it may appear that Adrian fell on harder times. He landed in a dispute with some of his descendants. Adrian had been appointed trustee and had problems with a sum of money that had been left for them.
Rockertsen lived longer than most of his generation, and must have been active in leading the town for 50 years. His time of death is reasonably clear, as he stepped down as mayor in 1594, "due to age and infirmity". The next year, his wife Margrethe is referred to as "widow".
Recommended reading: Henry Ofstad: Glimt: fra borgermester Adrian Rockertzsen Falkeners liv [Glimpses from the life of mayor Adrian Rockertzsen Falkener]. Eget forlag, 2008.