Person

Janusz I of Warsaw

c. 1346–1429 · 14th century · Also known as Janusz the Elder

Janusz I of Warsaw (c. 1346–1429), also called Janusz the Elder, was a Piast duke who ruled the northern and eastern part of Masovia from 1374. He made Warsaw his main residence, laying the foundations of its later role as the capital of Poland. A loyal ally of Poland and Lithuania, he fought against the Teutonic Order at the Battle of Grunwald in 1410.

Janusz I of Warsaw
Image: AnonymousUnknown author · Public domain · Wikimedia Commons

Mentioned in 1 state history

Duchy of Masovia

See also

Cite this entry
APA
The Epoch Institute. (2026). Janusz I of Warsaw. In The Epoch Institute Encyclopedia. https://the-epoch-institute.org/encyclopedia/janusz-i-of-warsaw
MLA
“Janusz I of Warsaw.” The Epoch Institute Encyclopedia, The Epoch Institute, 2026, https://the-epoch-institute.org/encyclopedia/janusz-i-of-warsaw. Accessed .
Chicago
The Epoch Institute. “Janusz I of Warsaw.” The Epoch Institute Encyclopedia. 2026. https://the-epoch-institute.org/encyclopedia/janusz-i-of-warsaw.
Harvard
The Epoch Institute (2026) ‘Janusz I of Warsaw’, The Epoch Institute Encyclopedia. Available at: https://the-epoch-institute.org/encyclopedia/janusz-i-of-warsaw (Accessed: ).

Last reviewed October 2026Random entry ↻