Age of Empires IV is a real-time strategy game that requires you to memorize tech trees to play effectively and get units out as soon as possible when you need them. However, each civilization has unique features and units, so remembering the prerequisites for each one can be difficult.

Full Holy Roman Empire Tech Tree

The tech tree below is sorted in ascending order by Civilization Age, then alphabetically by Building and the units/upgrades they provide at that Age. If a unit/upgrade is nested in another unit/upgrade, the parent list item is a prerequisite to the child list item.

Dark Age

The following buildings and units become available in the Dark Age.

  • Aachen Chapel (Landmark)BarracksDark AgeSpearmanHardened SpearmanVeteran Spearman (Castle Age)Elite Spearman (Imperial Age)Feudal AgeEarly Man-at-ArmsMan-at-Arms (Castle Age)Elite Man-at-Arms (Imperial Age)Castle AgeLandsknechtElite Landsknecht (Imperial AgeHeavy MacesTwo-Handed WeaponsImperial AgeRiveted Chain MailDockDark AgeFishing BoatTransport ShipFeudal AgeTrade ShipGalleyExtended LinesDrift Nets (Castle Age)Additional SailsFire StationsCastle AgeHulkDemonlition ShipArmored HullNavigator LookoutExtra BallistaImperial AgeCarrackChaser CannonsExplosivesFarmHouseLumber CampDark AgeForestryFeudal AgeDouble BroadaxLumber Preservation (Castle Age)Crosscut Saw (Imperial Age)Meinwerk Palace (Landmark)Feudal AgeBloomeryDecarbonization (Castle Age)Damascus Steel (Imperial Age)Steeled ArrowBalanced Projectiles (Castle Age)Platecutter Point (Imperial Age)Fitted LeatherworkInsulated Helm (Castle Age)Mastered Smiths (Imperial Age)Iron UndermeshWedge Rivets (Castle Age)Angled Surfaces (Imperial Age)Siege EngineeringMarching DrillsCastle AgeMilitary AcademyMillDark AgeSurvival TechniquesWheelbarrowFeudal AgeProfessional ScoutsHorticultureFertilization (Castle Age)Precision Cross-Breeding (Imperial Age)Mining CampFeudal AgeSpecialized PickAcid Distillation (Castle Age)Cupellation (Imperial Age)OutpostFeudal AgeArrow SlitsFortify OutpostCastle AgeSpringald EmplacementImperial AgeCannon EmplacementPalisade GatePalisade WallTown CenterDark AgeScoutVillagerPrelateFeudal AgeTextiles

Feudal Age

The following buildings and units become available in the Feudal Age.

  • Hardened SpearmanVeteran Spearman (Castle Age)Elite Spearman (Imperial Age)

  • Veteran Spearman (Castle Age)Elite Spearman (Imperial Age)

  • Elite Spearman (Imperial Age)

  • Man-at-Arms (Castle Age)Elite Man-at-Arms (Imperial Age)

  • Elite Man-at-Arms (Imperial Age)

  • Elite Landsknecht (Imperial Age

  • Drift Nets (Castle Age)

  • Lumber Preservation (Castle Age)Crosscut Saw (Imperial Age)

  • Crosscut Saw (Imperial Age)

  • Feudal AgeBloomeryDecarbonization (Castle Age)Damascus Steel (Imperial Age)Steeled ArrowBalanced Projectiles (Castle Age)Platecutter Point (Imperial Age)Fitted LeatherworkInsulated Helm (Castle Age)Mastered Smiths (Imperial Age)Iron UndermeshWedge Rivets (Castle Age)Angled Surfaces (Imperial Age)Siege EngineeringMarching DrillsCastle AgeMilitary Academy

  • Decarbonization (Castle Age)Damascus Steel (Imperial Age)

  • Damascus Steel (Imperial Age)

  • Balanced Projectiles (Castle Age)Platecutter Point (Imperial Age)

  • Platecutter Point (Imperial Age)

  • Insulated Helm (Castle Age)Mastered Smiths (Imperial Age)

  • Mastered Smiths (Imperial Age)

  • Wedge Rivets (Castle Age)Angled Surfaces (Imperial Age)

  • Angled Surfaces (Imperial Age)

  • Military Academy

  • Professional ScoutsHorticultureFertilization (Castle Age)Precision Cross-Breeding (Imperial Age)

  • Fertilization (Castle Age)Precision Cross-Breeding (Imperial Age)

  • Precision Cross-Breeding (Imperial Age)

  • Acid Distillation (Castle Age)Cupellation (Imperial Age)

  • Cupellation (Imperial Age)

  • ScoutVillagerPrelate

  • Archery RangeFeudal AgeArcherVeteran Archer (Castle Age)Elite Archer (Imperial Age)Castle AgeCrossbowmanElite Crossbowman (Imperial Age)Imperial AgeHand CannoneerBattering RamBlacksmithFeudal AgeBloomeryDecarbonization (Castle Age)Damascus Steel (Imperial Age)Steeled ArrowBalanced Projectiles (Castle Age)Platecutter Point (Imperial Age)Fitted LeatherworkInsulated Helm (Castle Age)Mastered Smiths (Imperial Age)Iron UndermeshWedge Rivets (Castle Age)Angled Surfaces (Imperial Age)Siege EngineeringCastle AgeMilitary AcademyBurgrave Palace (Landmark)Feudal AgeSpearmanHardened SpearmanVeteran Spearman (Castle Age)Elite Spearman (Imperial Age)Early Man-at-ArmsMan-at-Arms (Castle Age)Elite Man-at-Arms (Imperial Age)Castle AgeLandsknechtElite Landsknecht (Imperial Age)Heavy MacesTwo-Handed WeaponsImperial AgeRiveted Chain MailMarketFeudal AgeTraderRegnitz Cathedral (Landmark)Siege TowerStableFeudal AgeScoutHorsemanVeteran Horseman (Castle Age)Elite Horseman (Imperial Age)Castle AgeKnightElite Knight (Imperial Age)Stone WallStone Wall GateStone Wall Tower

Castle Age

The following buildings and units become available in the Castle Age.

  • Veteran Archer (Castle Age)Elite Archer (Imperial Age)

  • Elite Archer (Imperial Age)

  • Elite Crossbowman (Imperial Age)

  • Feudal AgeSpearmanHardened SpearmanVeteran Spearman (Castle Age)Elite Spearman (Imperial Age)Early Man-at-ArmsMan-at-Arms (Castle Age)Elite Man-at-Arms (Imperial Age)Castle AgeLandsknechtElite Landsknecht (Imperial Age)Heavy MacesTwo-Handed WeaponsImperial AgeRiveted Chain Mail

  • Elite Landsknecht (Imperial Age)

  • Veteran Horseman (Castle Age)Elite Horseman (Imperial Age)

  • Elite Horseman (Imperial Age)

  • Elite Knight (Imperial Age)

  • Elzbach PalaceCastle AgeSpringald EmplacementBoiling OilSlate and Stone ConstructionImperial AgeCannon EmplacementReinforced DefensesKeep Castle AgeSpringald EmplacementBoiling OilSlate and Stone ConstructionImperial AgeCannon EmplacementReinforced DefensesMonasteryCastle AgePrelateHerbal MedicineBenedictionDevoutnessInspired WarriorsImperial AgePietyTithe BarnsSiege WorkshopCastle AgeSpringaldMangonelCounterweight TrebuchetGreased AxlesImperial AgeBombardCulverinRoller Shutter TriggersAdjustable CrossbarsSiege WorksPalace of Swabia (Landmark)Dark AgeScoutVillagerImperial OfficerFeudal AgeTextiles

Imperial Age

The following buildings and units become available in the Imperial Age.

  • Dark AgeScoutVillagerImperial OfficerFeudal AgeTextiles

  • ScoutVillagerImperial Officer

  • Great Palace of Flensburg (Landmark)UniversityImperial AgeChemistryGeometryBiologyIncendiary ArrowsCourt ArchitectsElite Army Tactics

That’s the entire tech tree for the Holy Roman Empire Civilization!

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