Per Mertesacker made the game safe with a header soon after before substitute Olivier Giroud added a late fourth as the Gunners became the most successful side in the competition’s history with 12 wins.
Perhaps wary of repeating last season’s disastrous start against Hull City, which saw them go two goals behind, Arsene Wenger’s side began on the front foot in a frenetic opening 10 minutes and gradually cranked up the pressure on Shay Given’s goal with a series of corners and set-pieces.
The former Newcastle United goalkeeper – starting a second Cup final 17 years after his first, which also ended in defeat to Wenger’s side – was required to claw out Laurent Koscielny’s lofted header before Aaron Ramsey got across the returning Jores Okore to ripple the side-netting.
Ramsey scooped another effort over soon after, while Villa looked in vain to Christian Benteke as an outlet in a bid to relieve the pressure.
However, Given’s goal continued to lead a charmed life as Kieran Richardson blocked Walcott’s goalbound effort, only for the striker to open the scoring five minutes before the break.
Sanchez’s header dropped kindly in the box and Walcott made no mistake – ending Villa’s resistance with a powerful finish at the near post.
Arsenal began the second half as they ended the first – dominating possession and linking neatly up front – with Sanchez doubling the advantage in spectacular fashion.
A dipping effort from 30 yards had a perplexed Given beaten all ends up as the Chilean effectively wrapped up the victory with his 25th goal of an impressive debut season with the club.
Despite the introduction of Gabriel Agbonlahor for Charles N’Zogbia, Villa never looked like repeating Arsenal’s heroics of last year.
Instead, Mertesacker shook off Benteke’s attentions to flick Santi Cazorla’s corner beyond Given shortly after the hour before Giroud compounded a disappointing day for Villa with a clipped finish at the near post from fellow substitute Alex Oxlade-Chamberlain’s cross.
There could be no doubt Wenger’s men merited writing themselves into English football history as former Tottenham boss Tim Sherwood was denied a piece of silverware to end what has nonetheless been an impressive introduction to life at Villa Park.