Mezue ahịrịokwu na-esonụ: Mgbe nna ya nwụrụ n'afọ 1823, ọ gara Spen ebe ọ lụrụ ọgụ nwa oge na nnupụisi nnwere onwe megide ọchịchị ọchịchị aka ike nke Ferdinand nke Asaa; tupu ndị agha France ejide ya. N'afọ 1825, ọ nọ n'etiti otu ndị ọrụ afọ ofufo nke Ọchịagha Charles Fabvier na Marseille goro ka ha lụọ agha na Greek War of Independence. Ọ bịarutere Nauplion na 1825, na mbụ na-eje ozi na Colonel Auguste Regnaud de Saint-Jean d'Angély's cavalry dị ka Trooper. Myhrberg sonyere n'agha na Euboea na 1826, ọ lụkwara ọgụ na mgbalị enyemaka nke Siege nke Acropolis ebe ọ merụrụ ahụ. N'afọ 1826, e buliri ya n'ọkwa Lieutenant, ma mesịa soro n'agha ahụ ebe e merụrụ ya ahụ ọzọ. E merụrụ ya ahụ n'agha nke ugboro atọ n'agha nke Cape Colias, ebe e buliri ya n'ọkwa onye isi mgbe emechara ya. N'ọnwa Jenụwarị 1827, Myhrberg ghọrọ onye enyemaka nke Fabvier ma mesịa rụọ otu ọrụ ahụ maka Major General Thomas Gordon na Colonel Carl Wilhelm von Heideck. Myhrberg sonyere n'agha nke Phaleron na njem nke Chios ebe ọ pụtara ìhè. N'afọ 1829, Ioannis Kapodistrias họpụtara Myhrberg ka ọ bụrụ onye isi nke ebe e wusiri ike Palamidi. N'ịtụ egwu mmetụta na-arịwanye elu nke ndị otu Russia, Myhrberg hapụrụ Gris na 1831 iji sonye na Nchịkwa Nọvemba nke Polish. Obere ihe ka ama banyere oge a nke ndụ ya, dịka akụkọ akụkọ nke Anders Ramsay, Myhrberg lụrụ ọgụ na
Agha nke Ostrołęka. Ndị Russia jidere ya n'oge ụfọdụ n'oge agha ahụ, ma o jisiri ike gbaga Prussia nke na-anọghị n'ọchịchị, ma mesịa biri na France.