believed he would succeed in uniting the South Slavs living in Serbia, Montenegro, Austria-Hungary and the Ottoman Empire. In Vienna, en route to Belgrade, he was welcomed by a crowd of euphoric Serb and Croat students, who hailed him as "the first Yugoslav king". Reign Accession The royal couple's murder upset and shocked most of Europe, but many Serbs reacted enthusiastically. Russia immediately recognized the National Assembly's decision declaring Peter the next King of Serbia and expressed satisfaction that the inter-dynastic intrigues which had plagued the country since the early-19th century had been brought to an end. Austria-Hungary declared its neutrality on the matter, but privately, policymakers in Vienna expressed hope that Peter's accession would have a placating effect. The United Kingdom demanded that the chief conspirators be severely punished, and when the Royal Serbian Government neglected to carry out this request, the British severed all diplomatic ties. Several other European nations followed in the United Kingdom's footsteps and severed ties as well. Peter lacked the power or authority to punish the conspirators. He also felt a deep sense of obligation towards them, acknowledging that he would not have been able to assume the throne were it not for their actions. Coronation Peter was crowned in St. Michael's Cathedral in Belgrade, on . The coronation ceremony, the first in Serbia's modern history, aimed to demonstrate that a new era had begun. The year-long interval between Peter's return to Serbia and his coronation deliberately made the ceremony coincide with the 100th anniversary of the First Serbian Uprising with the hope of giving European statesmen time to come to terms with the palace coup. Nevertheless, only representatives of Montenegro and Bulgaria attended. New royal regalia, consisting of a crown, sceptre, orb and royal mantle, were commissioned specially for the occasion from the Parisian jewelers Falize Frères. Arnold Muir Wilson, the honorary Serbian consul in Sheffield, and his cameraman, Frank Mottershaw, filmed King Peter's procession and a parade following the coronation. This is the oldest surviving film recorded in Belgrade. According to film historian Paul Smith, it is also likely the first newsreel in history. Foreign affairs During the reign of Peter I the Kingdom of Serbia expanded to the south, incorporating much of Sandžak and Kosovo and Metohija in 1912 in the First Balkan War. Serbia temporarily controlled northern parts of Albania, but had to give away those parts to Albania in