Like everything else in our global economy... it's complicated.
Metzeler was bought out by Pirelli in 1986, but the brand still functions as a subsidiary of Pirelli.
Pirelli, in turn, was purchased by Chinese state-owned enterprise ChemChina in 2015 and functions as a subsidiary company.
Pirelli/Metzeler has factories all over the world -- Brazil, Romania, Germany, Italy, China, etc., so it's a total crapshoot where any given set of tires was made. The factories in China are the largest and newest, so odds are you'll get tires from China.
So far, I've seen a lot of folks complain about commie tires, but no one seems to have had any actual quality issues.
2002 Suzuki DL1000 V-Strom, Dark Metallic Space Blue
1983 Suzuki GS850G, Cosmic Blue
2005 KLR685, Aztec Red - Turd II.2, the ReReTurdening