Which ocean liner was the largest ship in the world when launched in 1858?

SS Great Eastern was the largest ship in the world when launched in 1858.

Designed by Isambard Kingdom Brunel and John Scott Russell, Great Eastern was built at Millwall on the River Thames. Its enormous size reflected Brunel’s ambition to create a vessel capable of carrying passengers and cargo between Britain and Australia without frequent refueling.

The ship used both paddle wheels and a screw propeller, along with sails, giving it multiple propulsion options. At about 692 feet long, it dwarfed most contemporary vessels. Technical and financial problems delayed its completion and limited its success as a commercial passenger ship.

Great Eastern later found important work laying transatlantic telegraph cables. Its size and engineering influenced later shipbuilding, even though it never became the profitable long-distance liner its designers had hoped to create.