Both he and his wife, Anne Gust Brown, have ancestral roots in both countries. "We like to go back and ... connect the dots," the Democratic governor said Friday.
Brown said he will meet with Enda Kenny, the prime minister of Ireland, as well as with labor officials and renewable energy experts in Germany, which has been a leader in green technology.
The governor, who has made the expansion of green energy a priority of his administration, said, "I want to find out how they've been able to accelerate their renewable energy."
Brown, 75, said he will also tour an automobile plant in Munich and visit the Dachau concentration camp.
Brown and the first lady will be joined by Brown's sister Kathleen Brown, the former California state treasurer. They plan to visit relatives and sites connected to Brown's great-grandfathers. One emigrated from Germany in 1848, and the other fled Ireland's potato famine for work as a gardener in Golden Gate Park.
"He lived in a mud hut," Brown said. "The Irish Catholics were pretty well oppressed."
The governor's office said Brown will cover his own costs. He led a trade mission to China earlier this year but has traveled relatively infrequently since taking office.
PHOTO: Gov. Jerry Brown talks to members of the press on Tuesday, April 23, 2013. The Sacramento Bee/Hector Amezcua