Oligomeric vinyl polynorbornene (2 to βΌ12 monomer units) was obtained via hydrooligomerization of norbornene (NB) using the cationic palladium complexes [Pd(PPh 3 ) n (NCCH 3 ) 4-n ](BF 4 ) 2 [n = 0 (1), 3 (2)] at different hydrogen pressures. The vinyl polymerization of norbornene (NB) in the ionic liquid N-butyl-Ntrimethylammonium bis(trifluoromethylsulfonyl)imide (BtMA + NTf 2 -) with [Pd(NCCH 3 ) 4 ](BF 4 ) 2 led to soluble polynorbornenes (with several hundred monomer units) at different temperatures and molar NB:Pd ratios. The norbornene derivative 5-vinyl-2-norbornene (VNB) was oligomerized in high yield with 1 in CH 3 NO 2 primarily through the (endocyclic) norbornene double bond but also through both the norbornene and (exocyclic) vinyl double bond for about every second monomer (by 1 H NMR). A 2D 1 H, 13 C-HSQC NMR analysis suggests a β€-hydrogen elimination after insertion of a norbornene double bond as chain-termination mechanism. The conversion of NB or VNB increased with temperature and a lower NB:Pd and VNB:Pd ratio, respectively. The vinyl double bond in VNB slowed down the insertion rate drastically when compared with NB (activity decrease by a factor of 10 2 ).