on 16 february 1940, the british royal navy breached norwegian neutrality in an operation to rescue 299 captive british sailors from the german auxiliary "altmark" in the norwegian jøssingfjorden. norwegian naval vessels observed the british operation, but did not intervene. angered by the altmark incident, adolf hitler the next day ordered the invasion of norway. among hitler's stated reasons for invading norway was a need to pre-empt a potential british landing in norway, a desire to secure the iron ore and other natural resources originating in or being supplied through norway, and to secure germany's northern flank while giving the kriegsmarine easier access to the atlantic ocean. hitler's concern about potential british landings in norway was encouraged by norwegian fascist leader vidkun quisling, who claimed that an alliance between the united kingdom and norway's labour party government was in the making. general nikolaus von falkenhorst was given overall command of the invasion of norway.