Unable either to stay in France or to move to Germany, Marx decided to emigrate to Brussels in Belgium in February 1845. However, to stay in Belgium he had to pledge not to publish anything on the subject of contemporary politics. In Brussels, Marx associated with other exiled socialists from across Europe, including Moses Hess, Karl Heinzen and Joseph Weydemeyer. In April 1845, Engels moved from Barmen in Germany to Brussels to join Marx and the growing cadre of members of the League of the Just now seeking home in Brussels. Later, Mary Burns, Engels' long-time companion, left Manchester, England to join Engels in Brussels.