No native Germans?

Actually, he may be right. Germany's President, Frank-Walter Steinmeier Said it to a group of Turkish residents meeting in Berlin.
World Wars one and two did a pretty good job of decimating the population of Germany. The young and able-bodied men went off to fight and ultimately die in far off lands while the women children and old folks remained home to be blown apart by daily and nightly bombing raids. When it all was over, Germany was occupied by American, British, French, Canadian and Russia troops, mostly horny young men, far from home, wives, girlfriends, with time to waste, money to blow, and enough dick to make prostitution the number one money maker. I exaggerate just a little.
That occupation continued for several generations, so if your great grandmother was a "pure German" in 1945, your grandmother was a half German half American girl who had fifteen "uncles" who stopped by to comfort mom and eventually her. Thus, your mother was 1/4 German, 1/4 American,  and half Canadian and you dear child are 1/8th German, 1/8th American, 1/4 Russian, and half Turk because they imported people to do the real work some years back... Just be glad you're not part French.