Conversation so far:
What did Sven Hedin do in nazi germany?
Hedin's conservative and pro-German views eventually translated into sympathy for the Third Reich.
what were Sven Hedin's influences?
His own views were shaped by traditionalist, Christian and conservative values.
what did Sven Hedin do for hitler?
Hedin met Adolf Hitler and other leading National Socialists repeatedly and was in regular correspondence with them.

Question: what did they correspond about?
Self-contained rewrite: what did Sven Hedin correspond with the Nazis about?