Yelagin Island was originally known as Mouse Island when St Petersburg was founded (1703). The Russian vice-chancellor Baron Pyotr Shafirov had a summer cottage on the island during the reign of Peter the Great (1682–1725). The island takes its name from one of its former owners, Count Ivan Yelagin, steward of the imperial household during the reign of Catherine the Great, who built the original Yelagin Palace (1780s). After the island was bought by Tsar Alexander I for his mother, Dowager Empress Maria Fyodorovna (1817), it became an imperial summer residence and the palace was reconstructed by Carlo Rossi (1818–22). After the death of Maria Fyodorovna (1828), Yelagin Island became the favourite place of Empress Alexandra Fyodorovna. Alexandra was the honorary chief of the Cavalier Guards Regiment, stationed in the nearby region of Novaya Derevnya. Every year, on the official regimental holidays – 5 September (St Elizabeth’s Day) and 5 October (St Zacharius’s Day) – a Te Deum was held on Yelagin Island. After the service, a military parade was held on Butter Meadow in front of the palace. After the parade, the empress congratulated the regiment. Illuminations were lit and music was played in the evening.