Which of the following cities has been a capital of Missouri?

St. Louis is historically recognized as a former capital of Missouri, which provides a rich context for understanding the state's governmental history. The city served as the capital from 1821, when Missouri was admitted to the Union, until 1826, before the capital was moved to Jefferson City, which remains the current capital.

St. Louis is significant not only for its temporary role as the capital but also for its development and growth during that period, which coincided with the westward expansion of the United States. The choice of St. Louis as a capital reflects the city’s importance as a center of trade and transportation at the time.

The other cities listed do not have this same historical significance regarding Missouri’s capital status. Kansas City,while one of the largest cities in Missouri, has never served as a capital. Similarly, Springfield and Columbia, although important cities within the state, have not held the role of capital at any point in Missouri's history. This factual context illustrates why St. Louis is the correct answer.