Games like Instant War
Games like Instant War include Broken Arrow, Europa Universalis IV, Sid Meier's Civilization VII, Sid Meier’s Civilization® VI, and Foxhole. We matched them by the tags players give Instant War on Steam (Strategy, 4X, Action RTS, Grand Strategy, and Wargame): closest matches first, and among equally close ones the better-known games.

Broken Arrow
Shared: Strategy · Wargame · Action RTS

Europa Universalis IV
Shared: Strategy · Grand Strategy · 4X

Sid Meier's Civilization VII
Shared: Strategy · Grand Strategy · 4X

Sid Meier’s Civilization® VI
Shared: Strategy · Grand Strategy · 4X

Foxhole
Shared: Wargame · Strategy · Military

Europa Universalis V
Shared: Strategy · Grand Strategy · Wargame

Stellaris
Shared: Strategy · Grand Strategy · 4X

Hearts of Iron IV
Shared: Strategy · Grand Strategy · Military

Company of Heroes 3
Shared: Strategy · Wargame · Action RTS

Total War: WARHAMMER
Shared: Strategy · 4X · Grand Strategy

Total War: THREE KINGDOMS
Shared: Strategy · Grand Strategy · Military

Total War: ROME REMASTERED
Shared: Strategy · Grand Strategy · 4X

Rebel Inc: Escalation
Shared: Strategy · 4X · Grand Strategy

Ara History Untold: Anniversary Edition
Shared: Strategy · 4X · Grand Strategy

ROMANCE OF THE THREE KINGDOMS XIV
Shared: Wargame · Grand Strategy · Strategy

WARNO
Shared: Strategy · Wargame · Military

Tempest Rising
Shared: Strategy · 3D · Action RTS

Heroes of Might and Magic: Olden Era
Shared: Strategy · Grand Strategy · 4X

HUMANKIND™
Shared: Strategy · 4X · Grand Strategy

Solar Nations 2
Shared: Strategy · Grand Strategy · 4X

Total War: WARHAMMER II
Shared: Strategy · Grand Strategy · War

Rising Storm 2: Vietnam
Shared: Wargame · Military · Strategy

Airships: Conquer the Skies
Shared: 4X · Wargame · Grand Strategy

Total War: EMPIRE – Definitive Edition
Shared: Strategy · Grand Strategy · Military