General Ion Antonescu came to power in September 1940. He signed the Tripartite Pact in November 1940.

As of 1941 Romania had 35 Czech R-1 tankettes, 126 R-2, 73 French R-35 (some were obtained from the Polish 21st Armored Battalion who had fled to Romania in 1939), and 60 FT-17s. The 1st Tank Regiment had the R-2s, the 2nd Tank Regiment had the R-35s, and the 1st Royal Cavalry had the R-1s.

Due to the lack of spare parts the R-35 were not part of the attack on Russia in 1941. After the drive on Odessa and the Don campaigns of 1942 the tanks were worn out. In September of 1942 PzKpfw IIIs and IVs were purchased from Germany. After the disaster at Stalingrad the Germans provided 50 PzKpfw 38(t)s in March 1943 to the 1st Tank Regiment.

From November 1943 PzKpfw IVs and StuG IIIs were supplied.

The Brasov factory in 1942 started to convert the R-2s to self-propelled anti-tank mounts with captured ZiS-3 76 mm Soviet guns. The Germans later provided Soviet T-60 tanks that had the Soviet F-22 76 mm added. They were designated TACAM (Tun autopropulsat cu afet mobile 76.2 mm) R-2 or T-60.

The 1st Armored Division remained in action until August 1944 when Romania switched sides.