After attending university, Reventlow was called to the Danish Court in 1665, where he rose through various positions of responsibility.

[2] In 1700, Reventlow was deeply involved in the negotiations for peace with Sweden during that country's naval blockade of Copenhagen, an early event in the Great Northern War.

Both France and the United Kingdom dealt extensively with Reventlow in their efforts to pressure Denmark to declare peace, in order to prevent a wider war from spreading into Europe.

In 1685, Reventlow used his influence as a councilor to the court on behalf of privateer Benjamin Raule (1634-1707), to promote Danish acquisition of the island of St. Thomas in the West Indies.

He married twice; with his first wife, Countess Anna Margarethe Gabel (1651-1678), he had two children: With his second wife, Sophie Amalie Hahn of Seekapm (1664-1722), he had three children: His sarcophagus in the Schleswig Cathedral (Schleswiger Dom) was designed by the renowned sculptor Thomas Quellinus.