The centenary of the outbreak of World War I was commemorated in Europe in late July and early August 2014. A century earlier, the July Crisis, which occurred after the assassination of Archduke Franz Ferdinand, had culminated in Austria-Hungary declaring war on the Kingdom of Serbia, which Austria-Hungary blamed for the assassination, on 28 July 1914. Over the following days and weeks, this action and the invasion of Luxembourg and Belgium by the German Empire led to a succession of other declarations of war that drew the major European powers into a worldwide conflict. A century later, governments in Europe held a series of official commemorative events to mark the occasion.