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A series of 18 lanthanide-containing 1D-coordination polymers ¹_∞[Ln₂(2–PyPzH)₄Cl₆], Ln = La, Nd, Sm, dinuclear polymorphic complexes α–, β–[Ln₂(2–PyPzH)₄Cl₆], Ln = Sm, Eu, Gd, α–[Tb₂(2–PyPzH)₄Cl₆], and [Gd₂(2–PyPzH)₃(2–PyPz)Cl₅], mononuclear complexes [Ce(2–PyPzH)₃Cl₃], [Ln(2–PyPzH)₂Cl₃], Ln = Tb, Dy, Ho, and Er, and salt-like complexes [Gd₃(2–PyPzH)₈Cl₈]Cl and [PyH][Tb(2–PyPzH)₂Cl₄] were obtained from the reaction of the respective lanthanide chloride with the 3–(2–pyridyl)pyrazole (2–PyPzH) ligand at different temperatures. An antenna effect through ligand-to-metal energy transfer was observed for several products, leading to the highest luminescence efficiency displayed by a quantum yield of 92% in [Tb(2–PyPzH)₂Cl₃]. The Ce³⁺ ion in the complex [Ce(2–PyPzH)₃Cl₃] exhibits a bright and orange 5d-based broadband emission with a maximum at around 600 nm, marking an example of a strong reduction of the 5d-excited states of Ce(III). The absorption spectroscopy shows ion-specific 4f–4f transitions, which can be assigned to Nd³⁺, Sm³⁺, Eu³⁺, Dy³⁺, Ho³⁺, and Er³⁺ in a wide spectral range from UV–VIS to the NIR region.