Dataset for the manuscript "Entanglement-induced collective many-body interference" (arXiv:2310.08630). The dataset comprises .csv files containing measurements relevant to supporting the manuscript. Enclosed within the ECMBI.zip file are two primary folders: CoincidencesDataSet: This directory contains subdirectories with raw data supporting single and coincidence count rates. Coincidences_PsiMinus: Polarization-entangled state set to the Bell state ψ- as specified in the manuscript. The directory includes the following subdirectories: Source1: Contains 48 CSV files of 60-second count rate measurements, sorted chronologically, when only the first photon source (Source 1) is employed. Each file contains count rate measurements for 31 different settings of the input polarization state. Within the set of 48 files, 16 files contain single-count and four-fold coincidence rates, 16 files contain three-fold coincidence rates, and 16 files contain two-fold coincidence rates. Half of the 48 files are corrected for multipair emissions (denoted by an additional Nin the file name: "*FoldN_*.csv") by rejecting events where there are coincidences in k>4 detectors (a total of 8 detectors is used). Source2: Contains 48 CSV files of 60-second count rate measurements, sorted chronologically, when only the second photon source (Source 2) is employed. Similar to Source1, it comprises 16 files for single-count and four-fold coincidence rates, 16 files for three-fold coincidence rates, and 16 files for two-fold coincidence rates. Again, half of the 48 files are corrected for multipair emissions (denoted by an additional N in the file name: "*FoldN_*.csv"). Source1Source2: Contains 120 CSV files of 60-second count rate measurements, sorted chronologically, when both photon sources (Source 1 and Source 2) are employed. Similar to the Source1 and Source2 folders, it consists of 40 files for single-count and four-fold coincidence rates, 40 files for three-fold coincidence rates, and 40 files for two-fold coincidence rates. Once more, half of the 120 files are corrected for multipair emissions (denoted by an additional N in the file name: "*FoldN_*.csv"). Coincidences_PsiPlus: Polarization-entangled state set to the Bell state ψ+ as specified in the manuscript. The structure mirrors that of Coincidences_PsiMinus. TomographyDataSet: This folder contains raw data supporting the fidelity measurement of the polarization-entangled states ψ+ and ψ-. Two tomography stages are used to perform measurements in 36 distinct combinations of the two detectors' measuring polarization basis (e.g., H, H; H, V; H, D; H, A; H, R; H, L; V, H; etc.). Tomography_PsiMinus: Polarization-entangled state set to the Bell state ψ-. The directory contains 6 CSV files for 6 different pumping power levels, each measuring 5-second two-fold coincidence rate for all 36 polarization bases. Tomography_PsiPlus: Polarization-entangled state set to the Bell state ψ+. The directory content mirrors Tomography_PsiMinus.