We investigated the influence of prepartum dietary oilseed supplementation on postpartum (pp) uterine inflammatory status (UIS) based on polymorphonuclear cells (PMN): normal (≤8% PMN) or subclinical endometritis (SCE; > 8% PMN), and associations among SCE, pro/anti-inflammatory cytokine gene expression and resumption of ovarian cyclicity. We hypothesized that feeding a diet containing sunflower seed (SUN; high linoleic acid) will induce pro-inflammatory effects in the early pp uterus facilitating early resumption of cyclicity. During late gestation (last 5 wk), Holstein cows received 1 of 3 diets supplemented with 8% DM rolled sunflower seed (SUN; n = 10) or canola seed (CAN; high oleic acid; n = 9), or no oilseed (CON; n = 9). Ovaries were scanned 2×/wk until 35 d pp to record first appearance of a 10 (DF) or 16 mm (PreOVF) follicle, and ovulation. Endometrial cell sampling was done 25 ± 1 d pp for cytology and gene expression. Data were analyzed using PROC MIXED, CORR and REG of SAS. Prepartum diets did not influence SCE incidence (SUN: 4/10; CAN: 4/9; CON: 3/9). The mRNA expressions of interleukin (IL)-1β, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α and interferon (INF)-γ were not affected (P > 0.05) by either prepartum diet or diet × UIS interaction. Feeding SUN prepartum hastened (P < 0.05) the establishment of PreOVF and increased the proportion of cows ovulating within 35 d pp. Regardless of prepartum diet, cows with SCE had higher (P < 0.05) mRNA expression of IL-1β, IL-8, IL-10 and TNF-α than normal cows. The intervals from calving to DF formation and first ovulation were not affected by UIS; however, PreOVF formed earlier (P < 0.01) in normal (13.2 ± 0.9) than in SCE (18.7 ± 1.4 d) cows. The mRNA expression of IL-1β, IL-8, IL-10 and TNF-α were positively correlated with each other (P < 0.01) and with PMN% (P < 0.07). The interval to PreOVF was determined by IL-1β, IL-8, IL-10, IFN-γ expression, PMN%, and the interval to DF. In summary, feeding SUN prepartum positively influenced pp ovarian function without affecting UIS. Increased endometrial expression of pro-inflammatory cytokines is likely linked to delayed establishment of PreOVF.