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The Artin conjecture asserts that the L-function of an irreducible, nontrivial representation a of a Galois group O)(F/F) of a number field F is entire. The Langlands conjectures, which very generally relate arithmetic L-functions to Lfunctions associated with automorphic forms, lead to a strong form of Artin's conjecture: there is a unique cuspidal automorphic representation ~z(a) of =L(s, 7r). From this point of view, the problem has been approached in two ways. In 1974. Deligne and Serre showed that for holomorphic g of weight one on GL(2) over Q, there exists a degree two representation a(~) of 0)(0/Q) such that L(s, a(~))=L(s, re). Then, in 1975, Langlands proved the existence of re(a) for a general class of degree two representations a of (r F arbitrary, whose image is solvable.In this paper, we show that the methods of Deligne and Serre can be extended to yield results for holomorphic cuspidal 7r of weight one on GL(2) over any totally real field F. Let d=[F: Q], and let ~z be a holomorphic cuspidal representation of weight one on GL(2) over F (the representationtheoretic version of a Hilbert modular cusp form of weight one). We construct a degree two representation c5(7z) of 05(F/F) with odd determinant and prove the following: if d is odd, then L(s,c,(rr))=L(s,~), and if d is even, then L(s, Ado cr(~))=L(s, Ad(rc)) where Ad: GL2(C)--+GL3(C ) is the adjoint map andAd (rt) denotes the Jacquet-Gelbart lift of rc to GL(3). We show further that foris known to satisfy the strong Artin conjecture.Hence the strong form of Artin's conjecture for degree two representations of (r with odd determinant and our results imply that there is a bijection between the set of holomorphic = of weight one and degree two a with odd determinant.The Deligne-Serre method consists of multiplying a Hecke eigenform f of weight one by an Eisenstein series E~ 1 whose q-expansion is congruent to one modulo a prime 1. This relates the Euler factors of L(s,f) to the reductions modulo l of the two-dimensional /-adic representations associated to higher weight forms on the cohomology of certain sheaves on the modular curves. For d> 1, however, the cohomology of the Hilbert modular varieties yields 2 <