Dirk II, count of Frisia and Holland

Dirk II or Theoderic II was a count in West Frisia, and ancestor of the counts of Holland. He was the son and heir of Dirk I and his wife Geva.

Frisia is a cross-border cultural region in Northwestern Europe. Stretching along the Wadden Sea, it encompasses the north of the Netherlands and parts of northwestern Germany. Wider definitions of "Frisia" may include the island of Rem and the other Danish Wadden Sea Islands. The region is traditionally inhabited by the Frisians, a West Germanic ethnic group.

The County of Holland was a state of the Holy Roman Empire from its inception until 1433. From 1433 onward it was part of the Burgundian Netherlands, from 1482 part of the Habsburg Netherlands and from 1581 onward the leading province of the Dutch Republic until the Batavian Revolution in 1795. The territory of the County of Holland corresponds roughly with the current provinces of North Holland and South Holland in the Netherlands.