Illumination assemblies, components, and related methods are described. An illumination assembly can include at least one solid state light-emitting device, and at least one light guide including a light homogenization region configured to receive light emitted by the solid state light-emitting device and including a light output boundary. The light homogenization region substantially uniformly distributes light outputted over the light output boundary. A wavelength converting material can be disposed within at least a portion of the light homogenization region. In some assemblies, a light extraction region can be configured to receive light from the light output boundary of the light homogenization region, and can have a length along which received light propagates and an emission surface through which light is emitted. The light extraction region can include a wavelength converting material disposed within at least a portion of the light extraction region.