Measurements of [CII]-158 μm at z ∼ 0.3 − 2.9 compared with [CII]-158 μm-LF estimates in the local universe (Hemmati et al. 2017) and z ∼ 5 (Yan et al. 2020). Also shown are theoretical predictions from C+ evolution models, including Gong et al. (2012) (blue hatches), Padmanabhan (2019) (dotted purple: best model, shaded band: uncertainty), Yang et al. (2022) (dash-dotted green), and Béthermin et al. (2022) (cyan line: De Looze et al. 2014 version; cyan dashed: high SFRD version at high z). Our 3σ upper limits disfavor high-temperature collisional excitation frameworks and best-fit empirical models calibrated to the Pullen et al. (2018), Yang et al. (2019)Planck measurement. The 1σ results are more consistent with SFR-scaling models, which calibrate C+ luminosity to the SFR of sources. Additionally, we show the COBE/FIRAS measurement of the monopole spectrum of the CIB as a function of wavelength, matched to the rest-frame redshift of [CII]-158 μm emission. The [CII]-158 μm contribution is likely no more than a few percent of the total CIB, with the intensity history evolving by less than an order of magnitude across cosmic moon.