These actions captured the attention of the Austrian Empire, which viewed Italy with great suspicion and worry, as irredentist claims by Italian nationalists were directed at key Austrian territories such as Venice, Trentino, and Trieste. In response to the growing strength of Sardinia—soon to be Italy—the Imperial Austrian Navy ordered two ironclads in 1860. This began a naval arms race between Austria and Italy, centered around the construction and acquisition of ironclads. This continued for the next six years, and by the time the war broke out between the two in 1866, Austria possessed seven ironclads to Italy's twelve.