UnitedKingdom_NationalFlag-Banner

1.9-1.12: /give @p minecraft:banner 1 4 {BlockEntityTag:{Patterns:[{Color:15,Pattern:"cr"},{Color:1,Pattern:"sc"},{Color:1,Pattern:"cs"},{Color:1,Pattern:"ms"}]}} 1.13+: /give @p minecraft:blue_banner{BlockEntityTag:{Patterns:[{Color:0,Pattern:"cr"},{Color:14,Pattern:"sc"},{Color:14,Pattern:"cs"},{Color:14,Pattern:"ms"}]}}