<P> In early seasons, under the influence of the A Song of Ice and Fire books, main characters were regularly killed off, and this was credited with developing tension among viewers . Later seasons, however, critics pointed out that certain characters had developed "plot armor", attributing this to the show's deviating from the books and becoming more of a traditional television series . The series also reflects the substantial death rates in war . </P> <P> Although the first season closely follows the events of the first novel, later seasons have made significant changes . According to David Benioff, the show is "about adapting the series as a whole and following the map George laid out for us and hitting the major milestones, but not necessarily each of the stops along the way". </P> <P> Tom Holland of The Guardian believes that the novels and their adaptations base aspects of their settings, characters, and plot on events in European history . Most of Westeros is reminiscent of high medieval Europe, from lands and cultures, to the palace intrigue, feudal system, castles, and knightly tournaments . A principal inspiration for the novels is the English Wars of the Roses (1455--85) between the houses of Lancaster and York, reflected in Martin's houses of Lannister and Stark . The scheming Cersei Lannister evokes Isabella, the "she - wolf of France" (1295--1358); Isabella and her family (particularly as portrayed in Maurice Druon's historical - novel series, The Accursed Kings) were also a main inspiration for Martin . </P> <P> Holland further proposes that other historical antecedents of series elements include Hadrian's Wall (which becomes Martin's Wall), the legend of Atlantis (ancient Valyria), Byzantine Greek fire ("wildfire"), Icelandic sagas of the Viking Age (the Ironborn), the Mongol hordes (the Dothraki), the Hundred Years' War (1337--1453) and the Italian Renaissance (c. 1400--1500). The series' popularity has been attributed, in part, to Martin's skill at fusing these elements into a seamless, credible version of alternate history . Martin acknowledges, "I take (history) and I file off the serial numbers and I turn it up to 11 ." </P>

Where did the idea of game of thrones come from
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