The city is a popular tourist destination, owing to its historic landmarks, beaches, and architecture.

Oceanside's origins date to 1798, when the Spanish founded the village of San Luis Rey with the establishment of Mission San Luis Rey de Francia by Fermín de Lasuén.

Following the U.S. conquest of California, the former mission lands were developed into an oceanfront resort and the community's name gradually changed to Oceanside.

Originally inhabited by Native Americans, Oceanside was first settled by the Luiseño peoples, or the Payomkawichum.

The city of Oceanside sits on the locality on the San Luis Rey River that the Luiseño called Tacayme, which contained the villages of Qée'ish (Keish) and 'ikáymay (Ikamal), in the San Luis Rey Mission area, Wiyóoya (Wiawio) at the mouth of the river, and Wi'áasamay (Wiasamai) and Waxáwmay (Wahaumai) at Guajome.

Spanish missionaries under Father Junípero Serra founded Mission San Luis Rey de Francia on a former site of a Luiseño Indian village on the banks of the San Luis Rey River called Keish according to the Portolà expedition who visited in the 1769.

In the early 19th century, the introduction of farming and grazing changed the landscape of what would become Oceanside.

Captain Pablo de la Portillà was appointed as administrator of San Luis Rey.

Following the departure of Padre Peyrí, relations between the Luiseños and the new civilian administration hugely deteriorated, resulting in their famed refusal to work for Captain Portillà in 1835.

[9] The town post office contains an oil-on-canvas mural, Air Mail, painted in 1937 by Elsie Seeds.

[11] In the 2010s, several mid-rise and high-rise housing and lodging projects were completed in the downtown area, with more to come.

As the crow flies, it is roughly the same distance from Aliso Viejo as it is to downtown San Diego.

The city has a municipal airport, a small craft harbor, one of the longest wooden piers in the west, golf courses, swimming pools, numerous parks, community centers, and extensive palm-lined beaches.

[citation needed] The Oceanside Unified School District provides instrumental music programs in grades 4–12.

Cesar Chavez Middle School, which is on the corner of Frazee and Oleander, will be built on 14 acres (5.7 ha), house 11 buildings totaling 84,000 square feet (7,800 m2), and will serve 1,000 6th–8th grade students.

The Oceanside Transit Center is a major railway interchange for long distance and commuter rail services.

Metrolink's commuter rail service connects Oceanside to many parts of Greater Los Angeles, while Coaster commuter rail serves northern and central San Diego County.

Oceanside Municipal Airport (OCN) is mainly used as a general aviation field.