Answer:
Great effect.
Step-by-step explanation:
There is a great effect of the arrival of the Polish, German and Venetian colonist have on the plot " Cornerstone of Civil rights" because these arrivals of the arrival of the Polish, German and Venetian colonist boost the struggle for civil rights. The Polish, German and Venetian colonist also helps in the struggle in gaining of civil rights so we can conclude that their arrivals have a good effect on the civil rights movement.