The imaginary worlds had their beginnings around 1826, when Charlotte and Emily, who shared a bed, invented simple unwritten plays, not unlike those created in many children's imaginary play. The very first of the Brontks' plays took most of the characters from toys, especially their brother Branwell's toy soldiers. The earliest surviving play that was written down, by Branwell, is set in Lorraine and concerns the imaginary intrigues and battles between would-be rulers, in the course of which the imagined events include a rebellion and a siege. As the Brontës' biographer Juliet Barker notes, most of the essential elements of their juvenile writings were already in place at that time, including political rivalries, battles, and rebellions that are played out within fantasy kingdoms (Juliet Barker, The Brontës, 1994, p. 152). Numerous sources were drawn upon. A particularly important inspiration was Blackwood's Magazine, a monthly journal containing a wide mixture of articles ranging from fiction to political satire and humour. Branwell's toy soldiers were given names and pressed into service as fictional characters.
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Our plays were established; Young Men, June, 1826; Our Fellows, July, 1827; Islanders, December, 1827. These are our three great plays, that are not kept secret. …The Young Men's play took its rise from some wooden soldiers Branwell had; Our Fellows from Æsop's Fables; and the Islanders from several events which happened. I will sketch out the origin of our plays more explicitly if I can. First, Young Men. Papa bought Branwell some wooden soldiers at Leeds; when Papa came home it was night, and we were in bed, so next morning Branwell came to our door with a box of soldiers. Emily and I jumped out of bed, and I snatched up one and exclaimed, 'This is the Duke of Wellington! This shall be the Duke!' When I had said this Emily likewise took one up and said it should be hers; when Anne came down, she said one should be hers. Mine was the prettiest of the whole, and the tallest, and the most perfect in every part. Emily's was a grave-looking fellow, and we called him 'Gravey.' Anne's was a queer little thing, much like herself, and we called him 'Waiting-boy.' Branwell chose his, and called him 'Bonaparte.' 
During this time Branwell acquired several sets of toy figures such as soldiers, Turkish musicians, and Indians. These toys were the impetus for the founding of the imaginary lands of Angria and Gondal. The children began to write plays about the figures, with Emily and Charlotte composing "bed plays" that they kept secret from the adults as well as from Branwell and Anne. In "Tales of the Islanders" (1829) Charlotte gave a history of the early plays, underscoring Emily's early affiliation with the works of Sir Walter Scott, for she chose the Isle of Arran for her island and Scott for her "cheif [sic] man." This affinity grew with Aunt Branwell's 1828 New Year's gift to "her dear little nephew and nieces," a copy of Scott's The Tales of a Grandfather (1827-1829). In addition to Scott's works the Brontë children drew material for their plays from the family library of Aesop's Fables, The Arabian Nights' Entertainment, and wood-engraver Thomas Bewick's History of British Birds. Their most important influence during these early years was most likely Blackwood's Magazine, whose satires, political commentaries, and extensive book reviews provided them with a wealth of detail that seeded their imaginations throughout their early years of creativity.
In 1831, after Charlotte left for Roe Head School, Emily and Anne began to concentrate their energies exclusively on the Gondal saga, distinct from the Angrian fantasies of their brother and sister, a special form of imaginative play in which the two younger sisters alone engaged for the remainder of their lives. Emily's first mention of Gondal occurs in her diary paper for 24 November 1834, a series of notes written by Emily and Anne about every four years and the earliest piece of Brontë's writing to have survived.
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Sally mosley is washing in the back kitchin. It is past Twelve o'clock Anne and I have not tid[i]ed ourselvs, done our bed work or done our lessons and we want to go out to play We are going to have for dinner Dinner Boiled Beef Turnips potato's and applepudding the Kitchin is in avery untidy state Anne and I have not Done our music exercise which consists of b majer Taby said on my putting a pen in her face Ya pitter pottering there instead of pilling a potate I answered O Dear, O Dear, O Dear I will derectly with that I get up, take a Knife and begin pilling (finished pilling the potatos papa going to walk Mr Sunderland expected. Anne and I say I wonder what we shall be like if all be well and what we shall be and where we shall be this year if all goes on well in the year 1874 -- in which year I shall be in my 57th year Anne will be going in her 55th year Branwell will be going in his 58th year And Charlotte in her 59th year hoping we shall all be well at that time We close our paper.
Emily and Anne November the 24 1834