USS Merrimac, sometimes incorrectly spelt Merrimack, was a cargo steamship that was built in 1894 in England as Solveig for Norwegian owners, and renamed Merrimac when a US shipowner acquired her in 1897.

A collier is a bulk cargo ship designed or used to carry coal. Early evidence of coal being transported by sea includes use of coal in London in 1306. In the fourteenth and fifteenth centuries, coal was shipped from the River Tyne to London and other destinations. Other ports also exported coal – for instance the Old Quay in Whitehaven harbour was built in 1634 for the loading of coal. London became highly reliant on the delivery of coal by sea – Samuel Pepys expressed concern in the winter of 1666–67 that war with the Dutch would prevent a fleet of 200 colliers getting through. In 1795, 4,395 cargoes of coal were delivered to London. By 1824, this number had risen to about 7,000; by 1839, it was over 9,000. The trade continued to the end of the twentieth century, with the last cargo of coal leaving the Port of Tyne in February, 2021.