A process for the production of 1,3-butadiene from a stream comprising ethylene, employing the following steps: a) carrying out a dimerization of the ethylene into n-butenes by bringing said stream into contact with a catalytic system based on a homogeneous catalyst, in order to produce an effluent comprising n-butenes, in which the ethylene dimerization is carried out: i) in the presence of a catalytic system comprising a catalyst based on alkyl titanate and an aluminium compound with formula AlR 3 or AlR 2 H in which each R is a hydrocarbyl radical; ii) in the presence of a catalytic system formed by a mixture of a first nickel compound selected from the group comprising the following formulae: (R 3 P) 2 NiY 2, (R 3 PO) 2 NiX 2, (R 3 AsO) 2 NiX 2, (pyridine) 2 NiX 2, (bipyridine)NiX 2, (phenanthroline)NiX 2 and a complex formed by a bicyclic nitrogen-containing compound with NiX 2, where R is a hydrocarbon group containing up to 20 carbon atoms, X is a halogen, Y is selected from halogens or hydrocarbon groups containing up to 20 carbon atoms and the pyridine, bipyridine and phenanthroline may or may not be substituted with one or more hydrocarbon groups, and a second compound represented by the formula R' z AlX y where x and y are whole numbers in the range 1 to 3, R' is a hydrocarbon group containing up to 20 carbon atoms and X is a halogen; b) carrying out a dehydrogenation of the n-butenes obtained in step a) by bringing at least a portion of said effluent into contact with a heterogeneous catalyst, in order to produce an effluent comprising 1,3-butadiene. a) carrying out a dimerization of the ethylene into n-butenes by bringing said stream into contact with a catalytic system based on a homogeneous catalyst, in order to produce an effluent comprising n-butenes, in which the ethylene dimerization is carried out: i) in the presence of a catalytic system comprising a catalyst based on alkyl titanate and an aluminium compound with formula AlR 3 or AlR 2 H in which each R is a hydrocarbyl radical; ii) in the presence of a catalytic system formed by a mixture of a first nickel compound selected from the group comprising the following formulae: (R 3 P) 2 NiY 2, (R 3 PO) 2 NiX 2, (R 3 AsO) 2 NiX 2, (pyridine) 2 NiX 2, (bipyridine)NiX 2, (phenanthroline)NiX 2 and a complex formed by a bicyclic nitrogen-containing compound with NiX 2, where R is a hydrocarbon group containing up to 20 carbon atoms, X is a halogen, Y is selected from halogens or hydrocarbon groups containing up to 20 carbon atoms and the pyridine, bipyridine and phenanthroline may or may not be substituted with one or more hydrocarbon groups, and a second compound represented by the formula R' z AlX y where x and y are whole numbers in the range 1 to 3, R' is a hydrocarbon group containing up to 20 carbon atoms and X is a halogen; i) in the presence of a catalytic system comprising a catalyst based on alkyl titanate and an aluminium compound with formula AlR 3 or AlR 2 H in which each R is a hydrocarbyl radical; ii) in the presence of a catalytic system formed by a mixture of a first nickel compound selected from the group comprising the following formulae: (R 3 P) 2 NiY 2, (R 3 PO) 2 NiX 2, (R 3 AsO) 2 NiX 2, (pyridine) 2 NiX 2, (bipyridine)NiX 2, (phenanthroline)NiX 2 and a complex formed by a bicyclic nitrogen-containing compound with NiX 2, where R is a hydrocarbon group containing up to 20 carbon atoms, X is a halogen, Y is selected from halogens or hydrocarbon groups containing up to 20 carbon atoms and the pyridine, bipyridine and phenanthroline may or may not be substituted with one or more hydrocarbon groups, and a second compound represented by the formula R' z AlX y where x and y are whole numbers in the range 1 to 3, R' is a hydrocarbon group containing up to 20 carbon atoms and X is a halogen; b) carrying out a dehydrogenation of the n-butenes obtained in step a) by bringing at least a portion of said effluent into contact with a heterogeneous catalyst, in order to produce an effluent comprising 1,3-butadiene.