Royals Prince William and the Duchess of Cambridge joined stars and members of the military at the world premiere of War Horse in London on Sunday.
But Steven Spielberg's movie, about a young boy and his horse Joey, has divided film critics in the UK.
A four-star review in the Daily Express praised the "touching saga of courage, loyalty and the truest of friendships".
Steven Spielberg speaks to BBC Breakfast: "I don't believe I've made a war movie"
But The Independent said Spielberg's adaptation of the hit play "adds
realism but loses some of the magic".
War Horse began life as a book, written by Michael Morpurgo. It was released in 1982 and adapted for the theatre in 2007.
Its run at the National Theatre in London was met with universal acclaim, with many praising the use of life-sized puppets to represent horses sent to the trenches during World War I.
The play transferred to Broadway in New York and won five Tony Awards. It is booked to run in London's West End for at least another year.
The new film was co-written by Four Weddings scribe Richard Curtis.
"Heart and craft"
Writing in the Express review, Allan Hunter said: "Michael Morpurgo's beloved novel has already inspired an extraordinary stage production.
"Spielberg cannot hope to compete with its theatrical intensity but his skill lies in a willingness to embrace the traditional virtues of the story with all his heart and craft."
Times reviewer Kate Muir called the film "a sweeping schmaltzy epic" but added its "power is undeniable".
Praising longtime Spielberg collaborator John Williams' emotive score and the cinematography of Janusz Kaminski, Muir said: "I teared up seven times and cried twice, the highest weepie score in my notebook."
However, not all critics were as moved. In hisGuardian review in December, Andrew Pulver accused Spielberg of directing a "lachrymose, buttery treatment" of the book and play.
He added: "From the first swooping shots of a chocolate-boxy English countryside, this War Horse is rooted in a buffed-up, sanded-down vision of rural England".
The Telegraph's Joe Marino was more positive saying the film "is genuine in its emotion, unflinching in its reality, epic in its grandiosity, effective in its performances, and imaginative in its storytelling".