The world's first lightvessel was the result of a business partnership between Robert Hamblin, an impoverished former barber and ship manager from King's Lynn, Norfolk, UK and David Avery, a regular investor in small projects. In 1730 the pair secured a government licence to moor a ship – with a prominent light affixed to it to serve as a navigation aid – at the Nore in the Thames mouth. Hamblin and Avery intended to profit from the vessel by collecting a fee from passing merchant vessels. The licence was opposed by Trinity House which considered that it possessed a monopoly on construction and maintenance of navigation aids in British waters. After extensive legal dispute the licence was revoked in 1732 and Trinity House assumed direct responsibility for the proposed lightship; Hamblin and Avery were granted nominal lease revenues in exchange. The Nore lightship commenced operations in 1734.
A further lightvessel was placed at the Dudgeon station, off the Norfolk coast, in 1736, with others following at Owers Bank (1788) and the Goodwin Sands (1793). Many others were commissioned during the nineteenth century, especially off England's east coast and the approaches to the Thames, where there were many treacherous shoals.
          Following their acquisition of the patent, all English and Welsh lightvessels were maintained by Trinity House, with the exception of the four vessels in the approaches to the River Mersey, which were maintained by the Mersey Docks and Harbour Board until 1973, and those in the Humber Estuary, which were the responsibility of the Humber Conservancy Board. In order to act as effective daymarks Trinity House lightvessels were painted red, with the station name in large white letters on the side of the hull, and a system of balls and cones at the masthead for identification. The first revolving light was fitted to the Swin Middle lightvessel in 1837: others used occulting or flashing lights. White lights were preferred for visibility though red and very occasionally green (as with the Mouse lightvessel) were also used.

         Communication with lightvessels proved to be a major problem for Trinity House; lightvessel crews were well-placed to observe ships in distress, but could not always alert lifeboats on shore. Attempts were made to run undersea cables between light vessels and shore stations but they proved unsuccesful. The world's first radio distress signal was transmitted by the East Goodwin lightvessel's radio operator on 17 March 1899, after the merchant vessel Elbe ran aground on the Goodwins, while on 30 April that year, the East Goodwin vessel transmitted a distress signal on its own behalf, when the SS R. F. Matthews rammed it in a dense fog. Safety was further improved by the development of more powerful lamps and through the replacement by foghorns of the gongs previously used as fog signals.
Crew
          Until the later 20th century, all Trinity House vessels were permanently manned. An 1861 article in the Cornhill Magazine described lightshipmen as being paid 55 shillings a month (in addition to drawing 1 shilling and sixpence a week "in lieu of 3 gallons of small-beer"): the vessels were supplied, and the crews relieved, once a month. It was also noted that "a general tone of decent, orderly and superior conduct" was observed, that the men were "very respectable ...]swearing and profane language are ... prohibited" and that every man was supplied with a Bible as well as "a library of varied and entertaining literature". By the start of the 20th century, Trinity House lightvessels had a crew of 11, of whom seven (a master and six ratings) would be on active duty at any one time. It was an extremely demanding and dangerous profession, and it would take 15 to 20 years of service to be promoted to master.
Replacement
          The majority of British lightvessels were decommissioned during the 1970s - 1980s and replaced with light floats or LANBY buoys, which were vastly cheaper to maintain: in 1974 at the time of Trinity House's original development project, lightship annual running costs at £30,000 were ten times those of the LANBY. The remaining UK lightvessels have now been converted to unmanned operation and most now use solar power.

          The first US lightship was put in place off of Willoughby Spit in Chesapeake Bay, Virginia, in 1820. Lightships remained in service in the United States until March 29, 1985, when the last ship, the Nantucket I, was decommissioned. During that period, lightships were operated by several branches of the government: by the Lighthouse Establishment from 1820 to 1852, the Lighthouse Board from 1852 to 1910, the Lighthouse Service from 1910 to 1939, and the Coast Guard from 1939 to 1985.
          The naming conventions used for lightships are not consistent. Until 1867, there was no uniform method to refer to individual lightships. Lightships in that period generally took the name of the station that they served, but occasionally other names. These names were not permanently assigned to an individual vessel. Rather, whenever a lightship was moved to a new station she took on that name. That made identifying individual ships nearly impossible. Beginning in 1867, lightship numbers (hull numbers) were assigned to ships still in service. These numbers are the primary means of identifying individual lightships across her various stations. In 1938, the Lighthouse Service retroactively allocated letter codes to the unnumbered lightships based on their research of available records, although some ships may have been lost or misidentified.[3] Even with the hull numbers, it is common to refer to a lightship by the name of the station it serves (or Relief, if it is a relief ship) and a few, such as the Nantucket I and Nantucket II have been given individual names.

          There were also light vessels off the coasts of Australia, Belgium, Germany, Sweden, Finland, Denmark, and Suriname.

           There was one known to have been in Canada. Bras d'Or was ordered by a New York ship owner who also ordered five other trawlers of the same class. Soon after her launch, the ship owner went bankrupt and Bras d'Or and her sisters were sold incomplete. She was finally finished in 1926 by the shipyard in Sorel, Quebec, for lightship service with the Department of Marine and Fisheries as Lightship No. 25 (which implies that there had been 24 lightvessels before her.) She was requisitioned on 15 September 1939 and was converted to an auxiliary minesweeper and received her new name and posting. Her first posting was to Halifax (former city), Nova Scotia, where she was tasked to patrol the harbour approaches to free up major warships for convoy duty. On 17 October 1940, Bras d'Or was ordered to proceed to Clarke City, Quebec, to shadow the Romanian freighter Inginer N. Vlassopol and to ensure that she made way to Sydney, Nova Scotia. While departing Rimouski Bras d'Or grounded herself on a shoal only minutes outside of port. She managed to free herself and continue on to Clarke City. She departed Clarke City on the 18th shadowing the Romanian freighter. Both ships encountered poor weather on the way to Sydney, and as darkness fell both ships turned on their navigation lights, an odd thing for a naval vessel to do during wartime. At 0350 on the 19th the First Officer of Inginer N. Vlassopol reported that the lights of Bras d'Or had suddenly vanished. It is believed that she had sustained unnoticed hull damage when she had run aground just outside Rimouski, and that it combined with the poor weather and sea conditions led to her destruction. 

​Information from wikipedia

Light vessels.