Italian unification was a sequence of stages between about 1848 and 1870, in which the Kingdom of Piedmont-Sardinia, volunteer forces, foreign powers and Austria’s position all played a part. The Kingdom of Italy was proclaimed in 1861, but Venetia and Rome joined later.
This topic belongs to core option A study pathways. Use your own syllabus year to see how much detail you need. For a model of how to weigh factors, see qualified causal language.
What was the sequence?
These are facts you can check in standard reference works.
- 1848 to 1849: Piedmont-Sardinia fought Austria and was defeated.
- 1852: Cavour became prime minister of Piedmont-Sardinia.
- 1858: Cavour and Napoleon III of France reached a secret understanding at Plombieres.
- 1859: war with Austria, with French support. Lombardy was added to Piedmont-Sardinia.
- 1860: plebiscites in central Italy, then Garibaldi’s expedition to Sicily and southern Italy, and the joining of these areas to the kingdom.
- March 1861: Victor Emmanuel II was proclaimed king of Italy.
- 1866: Venetia joined after Austria’s defeat in its war with Prussia.
- 1870: Rome joined after French troops left.
Which factors contributed?
Use short labels for each factor and say what it did.
| Factor | What it did | Evidence (fact) |
|---|---|---|
| Piedmont’s leadership | Gave unification a state and an army behind it | Piedmont-Sardinia led the wars and the plebiscites |
| French support | Made the 1859 war against Austria possible | French forces fought alongside Piedmont in 1859 |
| Garibaldi’s campaign | Brought the south into the new state | The 1860 expedition began in Sicily |
| Austria’s weakness | Allowed Venetia to join in 1866 | Austria lost its war with Prussia |
| Nationalist ideas | Built support for a single state | Plebiscites and volunteers in 1860 |
Worked example: weigh two factors
Question: How far was French support the main reason for success in 1859?
Step 1, state the claim. French support was very important for the 1859 war, but it was not the only reason Italy was unified.
Step 2, give the evidence. French forces fought in the 1859 war, and without them it is unlikely that Piedmont-Sardinia alone could have defeated Austria. That is a reasoned inference from the evidence, so use the word “unlikely” rather than “impossible”.
Step 3, set it against another factor. After 1859, the later stages depended on other things, such as Garibaldi’s campaign in 1860 and Austria’s defeat by Prussia in 1866. French help did not cover those.
Step 4, give the judgement. “French support was the most important factor for 1859, but across the whole period it was one of several, because later stages depended on Garibaldi’s campaign and on Austria’s defeat by Prussia.”
Notice the answer separates a fact (French forces fought in 1859), an inference (unlikely to succeed without them) and a judgement (relative importance).
The mistake to watch for
A student writes: “Cavour unified Italy.”
This is an overclaim. It leaves out Garibaldi, French support, Prussia’s defeat of Austria and the plebiscites. It also treats a debated interpretation as settled.
The correction is to name the person and the limit of his role: “Cavour, as prime minister of Piedmont-Sardinia, played a major part in the 1859 war, but unification also depended on Garibaldi’s campaign and on events outside Italy.” Historians weigh these roles differently, and your answer should show that you know it.
Check yourself
1. Which events happened in 1859 and which in 1860?
Show answer
1859: the war with Austria, with French support, and the addition of Lombardy. 1860: plebiscites in central Italy and Garibaldi’s expedition to Sicily and the south.
2. Why was the Kingdom of Italy in 1861 not the same as a fully unified Italy?
Show answer
Because Venetia (1866) and Rome (1870) had not yet joined. The 1861 proclamation was a milestone, not the end of the process.
3. Is “Garibaldi was more important than Cavour” a fact or an interpretation?
Show answer
An interpretation. It compares the importance of two people, which historians judge differently depending on how they weigh the evidence.
Where this leads next
Compare these events with German unification using the comparative outline lesson, then try the integrated practice set.
Weighing factors is a skill that improves with feedback on your own paragraphs, which is where a teacher in online one-to-one History tuition can help.