Did United States of America and British Empire exist in the same era?

Yes, the two civilizations both existed around 1776 CE.

Which lasted longer, United States of America or British Empire?

British Empire lasted longer (414 years).

United States of America: Kuzey Amerika; British Empire: Avrupa

United States of America (1776 CE – present) and British Empire (1583 CE – 1997 CE) lived in the same era.

	United States of America	British Empire
Period	1776 CE – present	1583 CE – 1997 CE
Duration	250 years	414 years
Region	Kuzey Amerika	Avrupa
Capital	Washington D.C.	Londra
Type	Republic	Empire
Government	Federal Başkanlık Cumhuriyeti	Anayasal Monarşi
Religion	Hristiyanlık (çeşitli)	Hristiyanlık (Anglikan)
Language	İngilizce	İngilizce
Peak population	331,000,000	458,000,000
Rulers	20	10

The world's first modern democratic republic. With its superpower status, the most influential state of the 20th and 21st centuries.

The empire with the most extensive territory in history. It was referred to as "the empire on which the sun never sets."

Did United States of America and British Empire exist in the same era?: Yes, the two civilizations both existed around 1776 CE.
Which lasted longer, United States of America or British Empire?: British Empire lasted longer (414 years).
Which regions did United States of America and British Empire rule?: United States of America: Kuzey Amerika; British Empire: Avrupa