Erik Julius Christian Scavenius (Danish pronunciation: [skæˈve̝ˀnius]; 13 July 1877 – 29 November 1962) was the Danish foreign minister from 1909 to 1910, 1913 to 1920 and 1940 to 1943, and prime minister from 1942 to 1943, during the occupation of Denmark until the Danish elected government ceased to function. He was the foreign minister during some of the most important periods of Denmark's modern history, including the First World War, the plebiscites over the return of northern Schleswig to Denmark, and the German occupation. Scavenius was a member of the Landsting (the upper house of the Danish parliament before 1953) from 1918 to 1920 and from 1925 to 1927 representing the Social Liberal Party. He was chairman of its party organization from 1922 to 1924.

Scavenius belonged to a tradition of elite governance that distrusted democratically elected politicians at a time when they were gaining power and influence. He believed that many of them were influenced by ignorant strains of populism and ill-equipped to face tough compromises and realities. For example, during the negotiations over the return of territory to Denmark following the First World War, he advocated a more cautious approach than many more nationalistic figures. He believed that areas that were mostly German should stay in Germany.

His policy of accommodation and compromise toward the Nazi occupation authorities in Denmark during the Second World War is one of the enduring controversies of Danish history. Some see it as a necessary compromise to protect the Danish state and people, but others see it as unnecessarily accommodating of totalitarian Nazi Germany.

The Scavenius family belongs to the Danish nobility. It was in the family tradition to work as a diplomat. Scavenius graduated in economics from the University of Copenhagen in 1901. Soon afterward, he became employed in the Danish Ministry of Foreign Affairs. He was a secretary at the Danish Embassy in Berlin from 1906 to 1908, a time forming his emphasis upon the primacy of Danish-German relations. Then, he became head of section in the ministry.

He was an envoy to Vienna and Rome from 1912 to 1913 and to Stockholm from 1924 to 1932. From 1932 to 1940, he was chairman of the board of the major daily Politiken. Scavenius was the owner of a large estate from 1915 to 1946. After 1945, he experienced marital and economic difficulties.

The appointment of the 32-year-old head of section Scavenius as minister of foreign affairs in the Radical Left Social Liberal cabinet Danish: Det Radikale Venstre (1909–1910) came as a surprise. He was reappointed when the party formed another cabinet in 1913. During World War I, he strongly put his efforts into the continuation of "the German course", a policy of keeping Denmark out of conflict with its neighbouring great power through adaptation. Among other things he supported giving in to the German demands to mine the Danish Straits in August 1914.

Scavenius was also an important figure as foreign minister during the negotiations surrounding the return of parts of Schleswig to Denmark following the war. Scavenius was one of the chief advocates of the Danish government's official position, advocating a return of only territories with clear Danish majorities (see Easter Crisis of 1920). That was opposed to the more "maximalist" position which demanded a return of all previously Danish territories south to the "Danevirke".

Scavenius became foreign minister again during most of the German occupation of Denmark. As such, he was the most important liaison between the Danish government and the German authorities. In addition, he was prime minister for some of the war as head of a coalition cabinet after the Telegram Crisis. He was more of a professional diplomat than an elected politician and held an elitist approach to government. At this time, the Social Liberal Party did not consider Scavenius to be its representative although the party accepted his line, along with the other coalition parties.