Why is complex multiplication of an elliptic curve called complex multiplication?

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Let $E$ be an elliptic curve over a field $k$. Let $\text{End}_k(E)$ denote the endomorphism ring of $E$, i.e., $$\text{End}_k(E) = \{\text{base point preserving morphism} \ f:E \to E\}.$$

Since multiplication by an integer $n$ is an endomorphism of $E$, we have an embedding $$ \mathbb{Z} \hookrightarrow \text{End}_k(E).$$

If this is a proper embedding, then we say the elliptic curve $E$ has complex multiplication.

Why is it called complex multiplication? Does it have anything to do with multiplication by a complex number?