In 1848–1849 the Honvédség (mostly made up of enthusiastic patriots with no prior military training) achieved incredible successes against better-trained and -equipped Austrian forces, despite the obvious advantage in numbers on the Austrian side. The Winter Campaign of Józef Bem and the Spring Campaign of Artúr Görgey are to this day taught at prestigious military schools around the globe, including at West Point Academy in the United States. Having suffered initial setbacks, including the loss of Pest-Buda, the Honvéd took advantage of the Austrians' lack of initiative and re-formed around the Debrecen-based Kossuth government. The Hungarians advanced again and by the end of spring 1849, Hungary was basically cleared of foreign forces, and would have achieved independence, were it not for the Russian intervention. At the request of the Austrian emperor Franz Joseph, the Russians invaded with a force of 190,000 soldiers – against the Honvédség's 135,000 – and decisively defeated Bem's Second Army in Transylvania, opening the path into the heart of Hungary. This way the Austrian-Russian coalition outnumbered Hungarian forces 3:1, which led to Hungary's surrender at Világos on 13 August 1849. Sándor Petőfi, the great Hungarian poet, went missing in action in the Battle of Segesvár, against invading Russian forces.