WEBOregon became the 33rd state of the U.S. on February 14, 1859. Today, with 4.2 million people over 98,000 square miles (250,000 km 2), Oregon is the ninth largest and 27th most populous U.S. state. The capital, Salem, is the third-most populous city in Oregon, with 175,535 residents. Portland, with 652,503, ranks as the 26th among U.S. cities.