To find the number of robberies in Springfield in 2013, we can let \( x \) represent the number of robberies in 2013. According to the problem, the robberies increased by 26% in 2014, leading to a total of 315 robberies that year.
We can set up the equation based on the increase:
\[ x + 0.26x = 315 \]
This simplifies to:
\[ 1.26x = 315 \]
Now, we can solve for \( x \):
\[ x = \frac{315}{1.26} \]
Calculating this gives:
\[ x = 250 \]
Thus, the number of robberies in Springfield in 2013 was \( \boxed{250} \).