Isaiah Hartenstein was born in Eugene, Oregon, to Florian (Flo) and Theresa Hartenstein. His father played basketball at the University of Oregon and professionally in Germany. That led the Hartenstein family to move to Germany in 2008. Isaiah Hartenstein later spent four seasons playing in Germany's youth and boys divisions from 2011-12 through 2014-15. He represented Germany in three FIBA events at the U16 and U18 levels, averaging 12.2 points and 9.1 rebounds per game. In 2016, he took part in the NBA's Basketball Without Borders camp. Learn more about Hartenstein by following him on Twitter and on Instagram (@Ipjh55).