Augustus Sol Invictus (born Austin Mitchell Gillespie; July 31, 1984) is an American far-right political activist, attorney, blogger, and white nationalist.

Invictus was a candidate for the Libertarian Party nomination in the 2016 United States Senate election in Florida. Local party chairman Adrian Wyllie resigned over his candidacy and the unwillingness of the party to disavow it. He lost overwhelmingly in the primary to opponent Paul Stanton, garnering 26.5% of votes cast.

In a press release from 2015, Invictus was accused by the Libertarian Party of Florida of advocating for eugenics and "state-sponsored murder". In April 2017, the Libertarian Party of Florida, following mediation, issued a retraction of the 2015 press release, stating that "it exceeded the mandate of the executive committee", and declaring that "Mr. Invictus has always been a member in good standing, is a past chair of the Libertarian Party of Orange County, a sponsor of the 2016 and 2017 LPF State Conventions, as well as a dedicated volunteer on the Legislative Review Committee." In July 2017, Invictus changed his party affiliation to Republican, announcing his candidacy for the 2018 United States Senate election in Florida.

Invictus was a headline speaker at the Unite the Right rally in Charlottesville, Virginia, on August 12, 2017, that ended with three deaths, and was ultimately tried and convicted for his actions that weekend. He has represented Marcus Faella, the former head of the white-supremacist group American Front, in court. Invictus is the publisher of The Revolutionary Conservative, a publication which calls for a violent uprising and states that its aim is to restore the American republic and defend Western civilization. He was controversial within the Libertarian Party for his neo-fascist political views and history of racist associations. He has been described by media reports as being associated with the alt-right movement. He has proposed the repeal of several amendments to the US Constitution, stipulating that only white male citizens should be allowed to vote or own real property.

Invictus graduated from the University of South Florida with a BA with honors in philosophy. Following his graduation, he attended DePaul University College of Law and graduated in 2011. While in law school, Invictus earned a fellowship at the International Human Rights Law Institute.^{[citation needed]}

He was managing partner of Imperium, P.A., a law firm he founded in 2013, until his retirement from the practice of law in 2017. Invictus is currently the publisher of The Revolutionary Conservative, a far-right publication with the stated aim of "restoring the American republic and defending Western Civilization".

Invictus was a headlined speaker at the Unite the Right rally in Charlottesville, Virginia, on August 12, 2017, where a white supremacist drove his vehicle into a crowd of counter-protesters, killing Heather Heyer. The Miami Herald wrote of Invictus's involvement in the fatal event that "the political fallout over Charlottesville may end whatever hopes for public office [Invictus] had."

On May 19, 2015, Invictus announced his campaign for the U.S Senate as a candidate for the Libertarian Party in the 2016 Florida election.