The rivers and woods in North Central Iowa were originally home to the Winnebago and Sioux Indians tribes but by the middle 1800's the push West by Europeans was underway. In 1853, John Long and John Bilford came from Illinois to claim timber and prairie land along the Winnebago River. John Long named the densely wooded area Masonic Grove in honor of the Order of Free Masons. That same year Long, Joseph Hewitt and George Brentner laid out a town on the same site renaming it Shibboleth. En route from Illinois with his family, Long's son, Mason, died. When he returned to Shibboleth, the town was renamed Masonville, in honor of his son. In the fall of 1853, John L. MacMillian and James Jenkinson built the first log cabin for MacMillian's family within the limits of what is now Mason City. When the first post office was erected, there were two towns in Iowa named Masonville, thus the present-day name of Mason City came into being. With an area of only one square mile, Mason City, Iowa became incorporated in 1870 with Darius B. Mason elected as the first mayor.

In 1866, the Mason City and Fort Dodge railroad line was established. The railroad opened the door for Mason City to grow quickly and became established as a significant retail and manufacturing center in the Midwest. The first industry, The Brick and Tile Company, got its start in 1886 using the natural resources abundant in the area. The lime, brick and tile business developed rapidly with the opening of The Northwestern State Portland Cement Plant in 1906 followed by the Lehigh Portland Cement Company in 1910. In 1911, the Colby Car manufacturing operation opened in the community. Competition was stiff and the factory was short lived but other industries were flourishing and Mason City's population was steadily increasing. By 1912, Mason City was shipping the largest freight tonnage in the state of Iowa and producing more brick and tile and more Portland cement than any city in the world. At one time there were nine brick and tile companies in Mason City. With the cement, brick and tile companies locating in Mason City, many immigrants from the southern and eastern parts of Europe came to find work here. "Lehigh Row" was housing set up for the immigrant workers on the grounds of the cement company and "White City" was the Northwestern's row houses for the workers.

At the turn of the century, in 1907, an architect came to the area to complete some design work for a prominent businessman in the community. This architect was Frank Lloyd Wright and Mason City was fortunate to have Wright and several of his associates, including Walter Burley Griffin and Barry Byrne, leave several examples of their unique prairie school architectural style behind. These works have become famous all over the world and still can be viewed today. Frank Lloyd Wright's works in the community include the only Prairie School designed home in Iowa, the Frank Lloyd Wright Stockman House which was constructed in 1908; The Park Inn Hotel, the only remaining hotel in the world designed by Wright built in 1910; and the City National Bank building, completed at the same time as the hotel. In addition, the largest group of Prairie School style designed homes on a unified site, Rock Crest & Rock Glen area, was developed.

By 1934 the Great Depression hit North Iowa along with the rest of the country. Throughout the Upper Midwest, John Dillinger and his gang were robbing from banks and making a name for themselves. Dillinger became somewhat of a hero to the depression weary farmers of the Midwest, as he would often destroy foreclosure records during bank robberies. It was on March 13, 1934 that "public enemy number one" came to Mason City and robbed the First National Bank. When they were done, Dillinger and his gang left $52,000 richer. Little did the gang know that the bank just happened to have more than $300,000 on hand that day. The First National Bank is now called the City Center and remains a historic treasure in downtown Mason City.

In 1954 a new breed of horse was introduced in Mason City. The Pony of the Americas (POA) grew to be one of the most popular breeds of horses in the country. Gentle and easy to train the POA's were especially suited for young people. This special breed of horse can be seen along with a variety of horses at the many equine events held at the North Iowa Fair Facility in Mason City throughout the year. In the 1950's and 1960's, the addition of the sugar beet industry and the pork packing industry helped Mason City to become the largest urban center between Des Moines and Minneapolis/St. Paul.

In 1951, Meredith Willson began working on a fun-filled musical story of "River City." Mason City is "The River City" of Meredith Willson's "The Music Man." The story was about a salesman trying to convince the citizens of River City to start a boys' band. The musical played several theaters in the East until Warner Brothers bought the movie rights and began production in 1961. On June 19, 1962 at the Palace Theater in Mason City, Iowa, Meredith Willson's hometown, "The Music Man" premiered. The cast of the movie traveled to Mason City for the gala event that was held in conjunction with the Mason City Band Festival. Meredith Willson's love of music lives on at The Music Man Square, where his personal memorabilia and a replica of the original movie streetscape are on display. Annually, Mason City hosts the Mason City Band Festival in tribute to the rich musical and cultural history the city is known for.