The considered constitutive modeling framework of finite viscoelasticity relies on three founda- tional ingredients: (1) strain energy density functions dictating elastic responses, (2) dissipation potentials capturing rate-dependent viscous losses, and (3) kinematic decomposition isolating inelastic deformation mechanisms. Building on the Green-Naghdi assumption, our approach achieves kinematic decomposition through the generalized strains, enabling a flexible sep- aration of elastic and inelastic deformations. The proposed model is able to recover classical finite linear viscoelasticity as a special case and allows calibrating both material moduli and kinematic decomposition to material-specific behaviors. This framework accommodates diverse viscoelastic phenomena across finite-strain regimes. Central to the viscous behavior is a non-negative, convex dissipation potential, formulated as a function of internal variable rates. It governs viscous evolution by satisfying the maximum dissipation principle through Lagrange multipliers and ensuring thermodynamic consistency of the Clausius-Planck inequality. Critically, the design of the dissipation potential seamlessly integrates non-Newtonian behaviors, such as the Bergström–Boyce model, through customizable power-law flow rules. This capability, unifying Newtonian and non-Newtonian viscosity within a single thermodynamic structure, positions the model as a generalized platform for modeling the rate-dependent effects of polymers, elastomers, and biological tissues under large deforma- tions. In this presentation, we validate the proposed framework using diverse experimental datasets, demonstrating its ability to capture nonlinear and non-Newtonian stress relaxation, creep, and hysteresis in viscoelastic materials. Additionally, we detail a robust computational algorithm for finite element implementation, enabling efficient simulation of complex boundary-value problems. The synergy between the Green-Naghdi kinematic assumption and a generalized dissipation potential advances the predictive modeling of finite viscoelasticity, offering a unified tool for both fundamental research and industrial applications.