On 28 August 1913, a contract for two steel freight steamships was signed by Newport News Shipbuilding and Dry Dock Company and the Mallory Steamship Company of the United States. "The vessel will be a single screw steamship of the hurricane deck type with straight stem and elliptical stern, and with deck houses amidship and aft for the crew accommodations...." The original specifications referred to the vessels as hulls No. 175 and No. 176. Hull No. 175 would eventually be named SS Neches and hull No. 176 became SS Medina. (Neches was lost in a collision with a British warship in 1918.)[3] The full contract for the vessels filled a 186-page volume and included the fittings commonly used in a ship for her era and also provision for tropical itineraries; for example, mosquito nets for the crew quarters.
On 11 August 1991, during the final night of the Doulos stop in the southern Philippine port of Zamboanga City, two of her foreign crewmembers were killed when a grenade thrown by members of the Abu Sayyaf Islamist terrorist group[4] exploded on stage during a performance by its Christian volunteers.[5] Four locals were killed[6] and 32 others were injured, including several crew members of the missionary ship.[5]
In 1995, in order to conform to the then new SOLAS regulations, she was fitted with a sprinkler system and combustible wall panels were removed and replaced. This unfortunately meant the loss of many of the wall murals that had been installed by Costa Lines.[7]
In 2006, while in Bahrain, a satellite communication system was installed.
| Total visitors | 21,461,212 | |
| Programme attendance | 3,500,898 | |
| Books sold | 1,513,446 | |
| Nautical miles sailed | 358,121 | |
| Total ports visited | 603 | |
| Countries and territories visited | 104 | |
| Different ports visited | 297 |
In 2009, while Doulos was in dry dock in Singapore, a survey conducted by the ship's classification society, RINA, found numerous significant problems with the ship's machinery, structure, and systems that would require work to have been completed by 31 December 2009 for the ship's certificates to be reissued and allow continue sailing. The shipyard servicing the Doulos would not accept the ship for repairs until September 2010; with the cost of the work exceeding 10 million euros, and the limited ministry that the ship would have after the repairs, it was decided to end the Doulos Ministry at the end of 2009, instead of 2010 as originally planned. The ship was offered for scrap at the end of 2009 when her operational certification expired. A caretaker crew remained with Doulos, expecting to sail her to the breakers.[8]
On 18 March 2010, Doulos escaped the breakers and had a new owner, Mr. Eric Saw, director and chief executive of BizNaz Resources International Pte Ltd in Singapore. She was renamed Doulos Phos (Servant of Light).[9] In 2015, BizNaz formed a joint venture with two other companies with the intention of converting the ship into a luxury hotel. That August the ship was towed out of Singapore to Batam, Indonesia, to be refurbished before moving to Bintan Island to become part of a US$25 million hotel resort. In October 2015 she went into drydock, where her hull was refurbished.[10] Steel reinforcement bracing was added inside her hull to support her weight on dry land. She was then towed to a location adjacent to the Bandar Bentan Telani Ferry Terminal. Using a system of pulling cables and air bags,[11] the ship was hoisted onto the promontory point.[12] This marked the end of her career as a floating ship.
In February 2016 the ship was officially renamed Doulos Phos, The Ship Hotel and began conversion into a luxury hotel.[13] The conversion is expected to retain the ship's bridge and engine room as part of the Maritime Heritage Museum. Decks A and B are used as the hotel. Originally scheduled to open in late 2016, workers and heavy equipment were still on the site in November 2017.[14] The hotel opened in 2019 with 104 rooms, all with a sea view.[15] The hotel closed during the COVID-19 pandemic in 2020 and appears to have been reopened since August 2022.