150s
The 150s ran from January 1, 150, to December 31, 159.
The Roman Empire was ruled by Antoninus Pius for the whole of this decade. The Roman Empire is relatively peaceful this decade, being in the middle of the Pax Romana and there being no major external wars. Claudius Ptolemy completed two major works this decade, the Geographia, the earliest known atlas, and the Almagest, a treatise accepted for over 1200 years.