RMS Atlantic was a steamship of the White Star Line that operated between Liverpool, United Kingdom and New York City.

The 3,707 ton ocean liner was built in Belfast, Ireland in 1870 and had a single propeller along with 4 masts rigged for sail, her single engine producing only 600 horsepower (447 kW). The vessel measured 420 feet (128 m) in length, with a beam of 40 feet (12.2 m) and draught of 31 feet (9.4 m).

On March 20, 1873 the Atlantic departed on her 19th voyage from Liverpool with 959 persons onboard, of whom 835 were passengers. En route, the crew decided to make port at Halifax, Nova Scotia to replenish coal for the steam-driven engine.

During the approach to Halifax on the evening of March 31 the captain and 3rd officer were on the bridge until midnight while the Atlantic made her way through a storm, experiencing limited visibility and heavy seas. Unbeknownst to the crew or passengers, the Atlantic was approximately 20 kilometres off-course to the west of Halifax Harbour and was proceeding at 12 knots (22 km/h) for Terence Bay, Nova Scotia .

At 02:00 local time on April 1, the Atlantic struck an underwater rock 50 metres from Meagher's Island . Lifeboats lowered by the crew were washed away and wrecked and the ship began to sink, killing 546 with 413 survivors, although exact numbers for persons onboard and those who perished vary depending upon sources.