Anthoni Schoonjans, nicknamed Parhasius was a Flemish painter known for his portraits as well as his history paintings. After training in Antwerp he had an international career, which saw him work in various countries in Europe including France, Italy, Germany, Austria, The Dutch Republic and Denmark. He was a court painter in Vienna, Copenhagen, Berlin and Düsseldorf.
Schoonjans was born in Ninove as the son of Joannes Schoonians, a wine merchant, and Anna de Gruytere and was baptized on 5 March 1655. He became in the Guild year 1668-1669 in Antwerp an apprentice of Erasmus Quellinus II and that master's son Jan-Erasmus Quellinus. From 1674 to 1677 the artist resided in Reims and he also spent some time in Paris.

By 1693 Schoonjans had moved to Vienna where he became the court painter of Emperor Leopold I in 1695. He was not a member of the court. During this period the Swiss painter Georg Gsell was his pupil. In April 1796 Schoonjans traveled to Frankfurt am Main, Kassel and Hamburg together with the Flemish painter Jan Frans van Douven. On 26 April 1796 he arrived at the final destination of his trip, Copenhagen. Schoonjans had been invited by the Danish court to paint portraits of the royal family. He later returned to Vienna where in 1697 he married the opera singer Franziska Maria Regina Schweyzer. He painted an altarpiece of the Martyrdom of St Sebastian for the St. Roch's Church and a Visitation of Mary for the St. Stephen's Cathedral in Vienna.

In 1704 Schoonjans traveled to England where he painted the stairwell in Montagu House, Bloomsbury and also made a portrait of a certain doctor Peeters. In 1706 Antoon Schoonjans is reported to have given some lessons to the Dutch floral painter Margareta Haverman.