Michiels entered military service at age 17 years, participated in the Battle of Waterloo, and in 1817 went to the island of Java, where he was directly involved in the conflict in Cirebon.
Michiels masuk dinas militer pada usia 17 tahun, ikut dalam Pertempuran Waterloo, dan pada tahun 1817 pergi ke Pulau Jawa, di mana ia terlibat langsung dalam konflik di Karesidenan Cirebon.