In 55 BCE, Julius Caesar led the first Roman invasion of Britain with two legions, but they were unable to establish a beachhead and had to fight the British forces in the surf. The following year, Caesar returned with a larger force of five legions, along with cavalry and improved landing craft. This time he was able to secure a beachhead and march inland, but the British harassed his forces and avoided direct engagement. While unable to subdue the Britons, Caesar's invasions established Roman influence and trade relations with Britain.

1. Julius Caesar’s Invasions

2. • Caesar’s ‘Conquest’
• Roman Perception of
Britain
• Romanization Begins

3. Evolution of the Roman Army
•Property owning farmers
•Reform of Marius (107 BCE)- all
citizens
•Cavalry of allies
•Government of provinces given
to high officials whose offices
arose from wealth not ability.
Officers of senatorial or
equestrian rank.
•91-89 BCE Italian property
owners gain citizenship

8. Invasion – 55 BCE
Legio VII Claudia Legio X Equestris

9. Significant Points
• In the first invasion, the Romans must fight ashore, actually
fighting it out in the surf.
• The campaigns, taken together, give a good example of how
Caesar learned from his mistakes the first time out. i.e.
specialized landing craft, larger force.
Capt. Carson, UIUC

10. Caesar, Veniti and Britain
• Threat to trade
• Veniti attack Roman fleet
• High, sturdy sailing vessels
• Roman fleet
• Oared vessels
• Use hooks to cut rigging

11. Roman Trireme

12. Background
•Cassivellaunus
•Ruler in the S.E. of Britain
•Subdued his eastern neighbors -- the “Trinovantes”
•Executed their King
•Banished his son and heir - “Mandubraces” - to the
continent
•Mandubraces goes to Caesar’s Camp begging for
help
•Caesar sends “Commius” - to stir up trouble

13. Policy Considerations
•Caesar part of the Roman triumvirate, attacks
Britain to enhance his reputation
•Caesar’s area is Gaul, has trouble with the Gallic
tribes, some leaders are using Britain as a
refuge, some mercenaries are coming from
there
•Invades to punish Britons for helping Gauls.
Invades to gain territory and fame
Capt. Carson, UIUC

14. Political Aspects
• Excitement of crossing the ‘Ocean’
• Keeps Caesar before the eyes of Rome
• Letter to the Senate
• Commentaries

15. Intelligence Shortcomings
• Campaigns preceded by poor intelligence
• Possible Sources
• Merchants – not forthcoming; warn Britons
• Volusenus fails to find Richborough
• Envoy, Commius, had influence with Atrebati but not tribes in the area of
invasion
• Campaigns work as intelligence gathering – not as conquest
Rose Mary Sheldon (2002): “Caesar, Intelligence, and Ancient
Britain,” International Journal of Intelligence and
CounterIntelligence, 15:1, 77-100

16. First Landing August 55 B.C.
• Embarks two Veteran Legions [VII, X] and some
cavalry.
• Launches following a “reconnaissance in force”
• Could not land since force was too small and had
been observed
• Caesar sails from Boulogne to the Dover area. Sees
British are there in force, so sails north for better beach
• He is tracked by British in chariots

17. Route

18. First Landing (Cont)
• Finds a better beach by Deal
• Must fight ashore
• Romans reluctant to leave ships
• Hand to hand fighting in the surf
• Transport ships cruise parallel to the shore
delivering supporting fire
• Romans finally secure a foot hold on dry land
• After three weeks, Caesar re-embarks and
leaves, accomplishing little

19. Landing

20. Heroes
• The Eagle standard bearer
• Caesius Scaeva – one man stand

21. The Fighting
• “Dismayed by these circumstances and altogether
untrained in this mode of battle, our men did not all exert
the same vigor and eagerness which they had been wont
to exert in engagements on dry ground.”
• Caesar ordered …”the enemy to be beaten off and driven
away, with slings, arrows, and engines: which plan was of
great service to our men “
• “All the Britains, indeed, dye themselves with woad,
which occasions a bluish color, and thereby have a more
terrible appearance in fight.

22. British and Roman Helmets

23. Artillery

24. Aftermath – First Invasion
• Envoys from enemy promise hostages
• Commius returns, reporting ill treatment
• Only two kingdoms provide hostages

25. Preparations: 2nd Invasion
•After building special flat-bottom, low freeboard,
minimum draft landing craft, Caesar attacks again
•5 legions (including veteran VII, X), plus 2,000
cavalry, for a total of about 22,000 troops
•A total of 800 ships to include 28 warships

26. Opposing forces
•2,000 war chariots
• Horses suitable for chariots
but not cavalry
•Briefly united tribes
•Some knowledge of Roman
tactics
• “Indirect warfare”

27. Second Invasion, July 54 B.C.
•Lands at the same beach
• Lands unopposed; (Britons seeing the size of the force decide not
to oppose)
• Caesar immediately marches inland 12 miles, catching Britons off
guard.
• 7th Legion attacks, hit with flank attack, but the veterans
withstand, improvise and take position
• Britons united under Cassivellaunus
• Storm damages Roman fleet. Not separate Naval commander
hurts repair effort. Lose 10 days.

28. Route

29. Bigbury

30. The Land Campaign
•Cassivellaunus divides force to attack base camp
and to get main body to pursue
• Cassivellaunus sees Caesar’s extreme sensitivity to the
security of base camp
• Realizes even with chariots, cannot win pitched fight
• Caesar pursues, conducts masterful forced crossing of
Thames, sends cavalry around flanks, brings up supporting
fires and conducts frontal assault

31. The Land Campaign (Cont)
• Romans unable to force the Britons into a pitched battle
• Roman base camp attacked, attack is beaten off, but commander sends
word to Caesar that he expects to be attacked again
• Caesar leaves main body, rushes back, surveys situation and decides to
abandon campaign
• Caesar withdraws after receiving few hostages, and a promise of
tribute

32. Strategic Considerations
• Virtually no strategic thought, at least for the first invasion. Land and
take over. Little planning.
• Was the first invasion a reconnaissance in force, or a true attempt to
invade
• For second invasion, Caesar comes to play, 5 legions a substantial
force

33. Operational Considerations
• First invasion hindered by lack of plan
• Few supplies, few troops, no landing craft
• Intelligence: recon force too small; no beach survey
• Deal chosen because looked good upon arrival
• No attempt at surprise
• Second invasion; planned.
• Larger fleet, larger force
• Landing craft, faster debarkation, close to beach.
• Uses same beach, brings supplies.

34. Tactical Considerations
• First landing, no landing plan, fight in the surf
• Good fire support in the first landing, brought the heavy stuff along on
the cargo vessels.
• Once fight is joined and Romans are organized, their superior training
and fighting skills are apparent and they prevail.
• The Britons chariots a factor until Romans learn how to counter

35. Tactical Considerations (Cont)
• Shortage of cavalry adequate recon and force screening difficult for
Romans
• Cassivellaunus conducts a textbook guerrilla fight
• Avoids decisive engagement
• Harasses foraging parties
• Strikes at the beachhead with a sufficient force to cause alarm

36. Technical Consideratons
•First time, no landing craft, rectified the second
time out.
•Returned with the gunships, not as critical the
second invasion.
•Good use of heavy artillery in crossing the
Thames.

37. Conclusions
•Security of beachhead and LOC to Gaul, primary
concerns for Caesar.
•Britons conduct guerrilla campaign, Cassivellaunus able
to recognize that he cannot conventionally defeat
Romans. Wins without winning a battle.
•Caesar commands both land and sea. Caused
problems in 54 after the storm
•Good naval gunfire support, earliest known example

38. Testudo

39. Conclusions (Cont)
•Somehow, Caesar’s reputation is not damaged.
•Flexibility of Cassivellaunus - exploited Roman
sensitivity to base camp
•Crossing of Thames excellent example of supporting
arms.
•As veteran troops gain familiarity with new
weapons(chariots in this case), they adapt tactics to
cope or overcome the new system. The new
weapon then loses most of its impact.

40. Conclusions (Cont)
•Romans aware of the pitfalls of invasion
•Opportunity for Roman and Romanized
merchants
•British leaders adopt aspects of Roman culture
•British policy reflects events in Rome
“…a Celtic-Gallic midget called Asterix (fix meant "king" in Celtic… for about
20 years has been beating up on Romans all over the place-to the delight of
citizens who have never quite forgotten, or forgiven, Caesar”
Dora Jane Hamblin. Smithsonian, May 1993

41. An Opposing View
• Purpose was only Caesar’s greed
• Loss of troops and ships
• Leaving Gaul might have threatened Italy
• Failure to find wealth (silver, gold, pearls?)
• Britain’s only asset – barbarous slaves who can neither write poetry
or music

42. After Caesar leaves
• Conflict in Gaul
• Troops disbanded to winter quarters however
• Approach of fall
• Enough supplies to overwinter
• Uprisings in 53 and 52 in Gaul prevent return

43. Evaluations
• Success
• 55 reconnaissance in force; 54 police action
• Trading patterns established
• Loyal allies cultivated
• 90 years of peace

44. Evaluation
• Failure
• No occupation for enforcement
• Did not successfully counteract chariot guerilla warfare
• Did not gain access to mineral resources
• Did not learn about agriculture, industry

45. Effects On Britain
• Subject to tribute
• Roman ‘technical assistance’ leads to improved coinage.
• Those who aided Rome benefit economically
• Those who opposed Rome wait their chances.

46. “British” Reaction
A kind of conquest
Caesar made here; but made not here his brag
Of 'came, and saw, and overcame.' With shame-
The first that ever touch'd him- he was carried
From off our coast, twice beaten; and his shipping-
Poor ignorant baubles!- on our terrible seas,
Like egg-shells mov'd upon their surges, crack'd
As easily 'gainst our rocks
Queen, Cymbeline Act III, Scene 1