The two-sided billboard, which depicts a large painting of Uncle Sam on both sides, is located beside the northbound lanes of Interstate 5 (I-5), near Exit 72, just outside of Chehalis. Alfred Hamilton began posting messages after I-5 was constructed across his turkey farm in the early 1960s to promote his "archconservative views in big block letters" .^[1] The first message he and his wife, Ruth, posted was based on their anger towards the government for funding welfare programs. Hamilton further resented the government for interfering with his ability to lease billboard space following Lady Bird Johnson's Highway Beautification Act of 1965.^[1] The New York Times described Hamilton as a "cranky crusader" who "loved a fight" and a "stubborn man, a turkey farmer with a big belly full of opinions".^[1] According to the paper, "Mr. Hamilton minced no words in attacking virtually everything and everyone that irritated him: gun control, the government and gays, Russians and radicals, Kissinger and Kerry."^[1] One of his friends recalled Hamilton's belief that "all Democrats were 'damn fools'", saying: "In many instances – and we were pretty close – I warned people not to get into discussions of religion and politics with him. He was so set in his ways that it was unusual."^[1] After Alfred Hamilton died in November 2004 at age 84, his family (who did not necessarily share all of his views) was initially uncertain if they would continue with the billboard's conservative content and upkeep; Hamilton's grandson has been posting new messages periodically ever since. I-5 motorists have been called a "captive audience", as congestion often causes traffic jams between Seattle and Portland, Oregon, both generally considered politically liberal. In 2003, a daily average of 50,000 motorists drove the 170-mile (274 km) stretch between the two cities, including northbound and southbound.^[1]

Over the years, the billboard has occasionally been moved or modified due to conflicts with the state and federal government.^[1] In 1995, The Seattle Times reported that Hamilton had sold his 130 acres (53 ha) of land between Centralia and Chehalis, and that the sign and other buildings on the land would be removed. The land had been in the Hamilton family since 1945. He and his wife moved to Alaska but continued to own nearby land.^[2] In the year leading up to the sale, billboard messages were changed once a month; before then, they were changed weekly.^[2] The billboard was moved to its current site just inside the Napavine city limits, south of Chehalis, in 1996.^[3]

Hamilton once stated: "I'm not trying to convert anyone to my way of thinking. But I want to make people think." After Hamilton's death in 2004, his son said, "I know the billboard had a lot of repercussions politically, from the state and the feds on down, because he voiced his opinions and sometimes he stepped on toes."^[1]

In June 2020, a petition listing 73,000 signatures was addressed to the Chehalis city council asking for the removal of the billboard. The request refers to purported statements posted on the sign as being racist and offensive while possibly creating a perception that the local communities are of such nature. An example shown in the petition was questioned for its accuracy and the Chehalis city council may not have jurisdiction as the sign resides solely in Napavine. The appearance of the petition coincided with a brush fire deliberately set in an attempt to burn down the billboard that same month.^[4]

The Billboards' conservative messages have targeted myriad subjects, including abortion, big government, and homosexuality.^[2] Some messages which have appeared on the sign include:

• "Be thankful you live in America" (1974)
• "Bill Caruth tells why you must stick to your guns" (1978), referring to opposition of gun control
• "Hasn't Gregoire cost taxpayers plenty of $ $ in boo-boos?"
• "Let's keep the Canal and give them Kissinger" (1970s)
• "My body My choice No forced vaccinations!" (2021)

The Kissinger message was Hamilton's favorite. The Gregoire message marked his last before his death in November, 2004.^[1]

The billboard has elicited considerable controversy over the years and several other attempts have been made by various individuals and groups to have it legally removed. Hamilton once said that feedback to the sign had been "95 percent positive".^[2] However, in 1985, Hamilton told The Oregonian that he had received threats over the sign.^[2] The billboard has been vandalized on numerous occasions and The Seattle Times reported that attempts had been made to burn it down, most recently in June, 2020.^[2] The New York Times called the billboard "a kind of grouchy chronicle of one man's one-sided take on things."^[1] Following Hamilton's death, one editorial contributor for the Seattle Post-Intelligencer wrote, "We thought the billboards cranky, but worth looking at. That billboard is what makes America better because it celebrates a founding principle of our nation, the First Amendment. We completely disagree with Hamilton's view of the world, but praise his discourse." The editorial began with the phrase "Uncle Sam is no more", but ended with, "Forget what we said above. 'Uncle Sam lives.'"^[1]

• Chehalis, Washington: Right-Wing Uncle Sam Billboard at RoadsideAmerica.com
• Seattle to Portland: The "Uncle Sam" Billboard at Seattlest (2008)