Is red hair exclusive to the scots/irish?

No, I've seen natural red hair in Germany, Scandinavia, Italy (yes, really. In fairer northern Italians), and in France.

People have been moving around for millenia, it's only to be expected that red hair would pop up in unexpected places.

Is red hair exclusive to the scots/irish?

No. There are redheads throughout the races, but are far more common in Northern European peoples.

Is red hair exclusive to the scots/irish?

No, all it takes is two copies of the recessive gene on chromosome 16. Obviously, more such recessive matches of chromosome 16 are available in Scotland and Ireland, but Napoleon Bonaparte, Cleopatra, Christopher Columbus, Judas Iscariot, Nero, Salome, and Stevtlana Stalin all had red hair. Of course, the pale skin associated with red hair may be advantagous in northern climates where sunlight is scarce. The United States has the highest incidence of red heads in the world.