Legion near Judea at time of Jesus

[Nathan Ross]

So what strength would Pilate take with him to Jerusalem?

As governor, he may well have had a small unit of singulares (bodyguards) drawn from the units under his command. If we assume he had five cohorts and an ala in various places around the province, and at least one of the cohorts was stationed in Jerusalem, he may not have needed to bring new troops to the city. Alternatively, if the bulk of his troops were in Caesarea and the coastal cities, he may have travelled to Jerusalem with a cohort - either 500 or 1000 strong, depending on how he judged the local situation. But most of this is guesswork - we don't have the evidence to know more!