The franchise revolves around an ensemble cast of anthropomorphic steam locomotives and other vehicles, including the main protagonist Thomas the Tank Engine, who work on the Island of Sodor.

The origins of the franchise date back to 1942, when two-year-old Christopher Awdry caught measles and was confined to a darkened room.

In response to questions his son asked about the rhymes, he began telling stories involving characters who later made their way to The Railway Series books.

The status of the project seemed uncertain, and while Stanley Pickard, Kaye & Ward's managing director at the time, told Awdry that he was "maintaining personal contact with Andrew and still had a slight hope that there might be a way out", Wilbert remained apprehensive, saying that "Once the Americans get hold of it the whole series would be vulgarised and ruined."

In the end, after several years of searching and having to place a second mortgage on her home, Allcroft raised sufficient funding from her local bank manager.

In October 2020, Mattel Television formed a new co-production partnership with Corus Entertainment's Nelvana and greenlit two new seasons for the Thomas & Friends series, consisting of 104 11-minute episodes and two hour-long specials.

Executive producer Christopher Keenan stated that it was, "crafted to appeal to contemporary audiences' sensibilities while maintaining Thomas' core brand ethos".

The land features several themed attractions, including an interactive dark ride and a roller coaster built by Sansei Technologies.

[29][30] From 2007 until 2017, Drusilla's Park near Alfriston, Sussex, England opened a railway ride featuring Thomas, Annie and Clarabel.

However, in late 2010, Six Flags began the process of removing Non-Warner Bros. licensed theming from its attractions, including Thomas & Friends.

The children's land features four flat rides themed around characters Thomas, Cranky, Flynn, and Harold, as well as a live entertainment show hosted by Sir Topham Hatt.

[citation needed] In January 2011, Thomas & Friends ranked as the number-one preschool toy property in the U.K. for the 11th year in a row.

[35] HiT Entertainment and later Mattel licenses "Day out with Thomas" events all over the world, at which visitors to heritage railways can meet and ride on a train hauled by replicas of the series' characters.

The Strasburg Rail Road in Lancaster, PA (USA) adapted Brooklyn Eastern District Terminal 15 in 1999 and introduced a replica of "Percy, the Small Engine" at the "Day Out With Thomas" event on 13 September 2014.

[37] Due to the increasing licensing fees and many other restrictions imposed by HiT including the need for "Sir Topham Hatts" to have auditions and the requirement for intensive Criminal Records Bureau checking, many heritage railways in the UK and overseas no longer run "Thomas" days.

A near life-sized Thomas carried Sophie Dahl to the stage to meet Sir Topham Hatt (Jonathan Ross) at the beginning of the show.

[41] In June and July 2001, the UK National Autistic Society conducted a survey of 81 parents of children with autism and Asperger syndrome to investigate their putative 'special relationship' with Thomas the Tank Engine.