Straža was established in the winter of 1716–17 by the Austrian imperial army as a base for soldiers sent to protect the town of Palanka from advancing Ottoman troops. After the army was recalled, several soldiers and artisans remained to form the settlement of Lagerdorf. The historian Borovski confirms that after the Ottomans were expelled, the settlement was colonized by Germans.[citation needed] By 1734, the settlement already had its own post office and a German mill was built near the Karaš River.
By 1744, Romanian settlers began to move into the settlement mostly from the Oltenia province in lesser Wallachia. By 1782, the settlement's population swelled to over 1,000 people, 917 of which were Eastern Orthodox. It was controlled by the Ottomans between 1787–88.
In October 1848, Serbian troops from Alibunar were stationed in the settlement because of advancing Hungarian troops. The Serb army was nearly destroyed by Hungarian troops under the leadership of the general Jovan Damjanić (a Serb by origin).
In 1880, Lagerdorf was renamed Straža (Straja in Romanian) and was referred to as Temes-Strazsa by the Hungarians in 1894 and Temesor in 1911. Name Straža itself is of Serbian origin (meaning "sentinel").
In 1854, the settlement's population was 1,195, in 1869, it reached 1,242, in 1880, the population was 1,510, in 1900 it was 1,606, and by 1910 the population was 1,678. During World War I, 70 soldiers from Straža lost their lives. In 1921, a total of 1,482 people lived in the settlement: 1,389 Romanians, 17 Serbs, 14 Hungarians, 10 Germans, and 52 others of various nationalities.