We consider concentrated vorticities for the Euler equation on a smooth domain Ω ⊂ R 2 in the form ofsupported on well-separated vortical domains Ωj , j = 1, . . . , N , of small diameters O(rj ). A conformal mapping framework is set up to study this free boundary problem with Ωj being part of unknowns. For any given vorticities µ1, . . . , µN and small r1, . . . , rN ∈ R + , through a perturbation approach, we obtain such piecewise constant steady vortex patches as well as piecewise smooth Lipschitz steady vorticities, both concentrated near nondegenerate critical configurations of the Kirchhoff-Routh Hamiltonian function. When vortex patch evolution is considered as the boundary dynamics of ∂Ωj , through an invariant subspace decomposition, it is also proved that the spectral/linear stability of such steady vortex patches is largely determined by that of the 2N -dimensional linearized point vortex dynamics, while the motion is highly oscillatory in the 2N -codim directions corresponding to the vortical domain shapes.