United Kingdom and France declare war on Russia, beginning their Crimean War intervention

Background. The conflict originated from Russian occupation of the Danubian Principalities in July 1853. Public outrage over the annihilation of the Ottoman squadron at Sinop compelled Britain and France to intervene. On 27 February 1854, the two nations demanded Russian withdrawal. When Russia ignored this ultimatum, the diplomatic situation escalated, leading to formal declarations of war in late March 1854.

Political Context. French Emperor Napoleon III sought to restore France's grandeur, initiating the events that led to the war. The Second French Empire, established in 1852, provided the political framework for this intervention. Britain and France acted as an alliance, joining the Ottoman Empire against Russia. Their entry transformed a regional dispute into a broader European conflict involving major powers.

Diplomatic Sequence. The declarations occurred in consecutive days. Britain declared war on 27 March 1854, followed by France on 28 March 1854. These actions were responses to Russia's failure to comply with the Anglo-French ultimatum regarding the Danubian Principalities. The sequence marked the transition from diplomatic pressure to active military engagement, with naval operations commencing shortly after the declarations.