In Vicky, pops only migrate to your most recently "de-colonized" region. In order to get them to move themselves around your country you need to make sure there's a shortage of jobs in the region you want to evict them from and a lot of jobs elsewhere in the country.
The problem is Vicky Revolutions doesn't allow for flexibility like the original did. The problem isn't internal migration but immigration from say Ireland to Massachusetts and Italy to NY and both are like 99% Protestant and 95% Yankee and its 1900. Revolutions doesn't allow for you to build factories unless the ruling party is state capitalist or planned economy. In 1881 both the GOP and the Dems are Lassiez Faire(Of course I change these from time to time to add more fun to the mix, but only btw Lassiez Faire and Interventionist). Immigration is usually dead in Revolutions for some reason with the exception of California, Alaska and Siberia(For some reason the Chinese flock to these three regions and the last 2 make no sense at all)
Plus why is my economy always stagnated. Is it my fear of debt. I always slide the Education slider to 100% to gain a tech edge. Crime, Military and Social spending(none existent in 1881 except 12 hour workday which I usually lower to 10 or 8 after I discover an off setting technology like "Shift work") usually take a hit to keep my budget balanced with usally a 100 surplus or more. I am the king of unfunded mandates. Tariffs I usually place at 25% or more(A requirement to get those pesky capitalist to invest) and I try to eliminate the income taxes or make them as low as possible(Don't have a choice cause the only way to build factories is via Capitalists thanks to game restrictions, mentioned above) and if the rich rate is higher then 25% nothing is built. I have tried more socialist policies with the sliders for taxes being at 75% for rich, 50% for Middle Class, and 25% for the poor; Tarriffs at 100% and -25%; plus spending jacked up and the result was not stagnation but shrinking.
I am seriously considering uninstalling Vicotoria Revolutions and returning to the original version An Empire Under the Sun.