Warmians (also Warmi) are one of the Prussian clans.

They live in Warmia (Polish: Warmia, Latin: Varmia, German: Ermland, Lithuanian: Varmė), a territory since 1945 largely in Poland.

It is situated between the Vistula Lagoon, Łyna and Pasłęka Rivers.

Soon after arrival of the first dukes of the Polans in Poland, centuries of Polish attempts at conquest of the native Prussians begin in 997.

The preferred method is to try to convert the still heathen Prussians to Christianity, and thereby also acquire their land.

A number of crusades follow, called by Konrad of Masovia, as well as attacks on Prussian land of the Yotvingians, which later becomes Polish Podlasie and of the Sudovians and Galindians.

To speed up and enforce this pressure on Prussians and Pomeranians, the duke Konrad, who had already called for crusade in 1209, now callsin the Teutonic Order.The Warmians, along with the other Prussians, are conquered by the Teutonic Knights, a crusading military order directly under the pope.

The Knights conquer the Prussians and convert them to Christianity.

Many cities and towns are built and the population increases by bringing in colonists from Germany, other countries of Europe, as well as from Poland.

The Prussians are eventually assimilated by the colonists and the Old Prussian language becomes extinct by the end of the seventeenth century or beginning of the eighteenth century.