Leicester Tigers centre Allen, also a winner of the tournament in 2008, played in all three games as the Saxons lifted the Churchill Cup for a fifth time in New Jersey.
Saxons, captained by Tigers summer signing George Skivington, scored four tries in the final, through Nick Abendanon, Alex Goode, Jon Clarke and Luke Narraway, with Stephen Myler landing three conversions and four penalties.
Head coach Stuart Lancaster said: "It's a fantastic achievement. Three weeks ago we met in a Heathrow hotel with disappointed players not making the senior tour and young players who came in straight from the Premiership and collectively to put all that together and form a team is great. I'm really proud.”
England Saxons
15 Alex Goode (Saracens)
14 James Simpson-Daniel (Gloucester Rugby)
13 Jon Clarke (Northampton Saints)
12 Anthony Allen (Leicester Tigers)
11 Nick Abendanon (Bath Rugby)
10 Stephen Myler (Northampton Saints)
9 Lee Dickson (Northampton Saints)
1 Nick Wood (Gloucester Rugby)
2 Andy Titterrell (Leeds Carnegie)
3 Alex Corbiserio (London Irish)
4 James Hudson (Newcastle Falcons)
5 George Skivington (London Wasps, captain)
6 Tom Wood (Worcester Warriors)
7 Andy Saull (Saracens)
8 Luke Narraway (Gloucester Rugby)
Replacements
16 Rob Vickers (Newcastle Falcons)
17 Duncan Bell (Bath Rugby)
18 Graham Kitchener (Worcester Warriors)
19 Kearnan Myall (Leeds Carnegie)
20 Micky Young (Newcastle Falcons)
21 Ollie Smith (Harlequins)
22 Tom Varndell (London Wasps)
