Despite the region's recent past being scarred by sectarian bloodshed over British control, a fragile calm has maintained since 1998.
As nationalists prepare to head the devolved government in Belfast for the first time, his 40th visit comes at a time when unionists faithful to the Crown .
However, the king conveyed a message to political leaders at Hillsborough Castle, his official residence in Northern Ireland.
He informed the people of Northern Ireland, "I take up my new duties resolved to seek the wellbeing of all the citizens of Northern Ireland."
It was widely regarded as a major step forward in preserving the fragile peace in Northern Ireland that the queen's 2011 visit to Ireland.
Crowds gathered at Hillsborough early to catch a glimpse of Charles and his wife, Queen Consort Camilla.