Johannes Opdam
Dutch murderer
Johannes Franciscus Alphonsus Marinus (John) Opdam (1916-1983) was a Dutch murderer.
Early life
Opdam was born in October 1916 in Surabaya, Dutch East Indies. In 1936, he moved to the Netherlands. There he studied medicine and married Arnolda van Eyl, a teacher's daughter.
First murder
During his wife's vacation in 1951, Opdam had an affair with the couple's maid, Nellie. Mrs. Opdam found out, but being a devoted Catholic, there was never any question of a divorce. Instead, Nellie was sacked. This did not stop Opdam from continuing his affair with the girl. In 1952, Mrs.
This brief starts where responsible research should: with the source description of “Johannes Opdam” as dutch murderer. Everything that follows is an evidence route, not borrowed authority.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jul 8, 2026. The linked authority identifier is Q6216886. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1916, 1983, 1936 and 1951.
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This entry incorporates text from “Johannes Opdam” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.