Sweetland held federal and labor-relations appointments between 1940 and 1943 and then joined the American Red Cross, serving in the Pacific theater of operations for two years.

[1] He won election to the Oregon State Senate in 1954 and re-election in 1958 to a second four-year term, spending a total of ten years in the legislature.

[1] Sweetland wanted to run for U.S. Congress in Oregon's 3rd Congressional district in 1954, but was dissuaded by some Democratic peers, including Howard Morgan and State Senator Richard Neuberger, who feared that, especially during the time of "McCarthyism", Sweetland's past Socialist ties would result in his defeat and that of other Democrats just as the party was beginning its rise.

During his years as a part-time Oregon legislator, Sweetland was a newspaper publisher in Milwaukie (his home), while also owning papers in Newport, and Molalla.

[10] As a prominent Democrat in one of the few states to hold presidential primaries at that time, Sweetland was contacted by candidates such as Adlai Stevenson, W. Averell Harriman, Estes Kefauver and their staffs.

Kennedy won the nomination, but upset Sweetland and other liberals by picking the runner-up, Senator Lyndon Johnson, as his running mate.

He and his family moved to San Mateo, California, in 1965, where Sweetland served as the National Education Association (NEA) representative to 13 states in the west until mandatory retirement in 1975.

[2] In that role he advocated the use of federal money to provide support to schools to encourage them to teach English as a second language in certain situations.

[1] After leaving the NEA he founded Western Wilderness Products, in San Mateo where he worked gathering rare plants until 1994.

[1] Sweetland returned to Oregon in 1994 and spent his final years as an elder statesman, including an unsuccessful run for his old state senate seat at age 88 in 1998.

[8][11] Sweetland was very active in organizations such as the Democratic Party of Oregon, The City Club of Portland, and the Wayne Morse Historical Park in Eugene.

Toward the end of his life, a scholarship was established in Sweetland's name at Portland State University, funded by his friends, most prominently King (NBC) Broadcasting executive Ancil Payne of Seattle.