The steady shear stress ( a) and first normal stress difference (N-1) of a thermotropic liquid-crystalline polyester, poly[( phenylsulfonyl)-p-phenylene l,10-decamethylene-bis (4-oxybenzoate)l (PSHQ10), in both the isotropic and nematic regions were measured as a function of shear rate (gamma), using a cone-and-plate rheometer. For the study, PSHQ10 was synthesized via solution polymerization in our laboratory. The PSHQ10 was found to have (a) the weight-average molecular weight of 45,000 relative to polystyrene standards and a polydispersity index of 2, (b) a glass transition temperature of 88 degrees C, (c) a melting point of 115 degrees C, and (d) a nematic-to-isotropic transition temperature of 175 degrees C. For the measurements of sigma and N-1 in the nematic region of PSHQ10, its initial conditions for the startup of shear flow was controlled by (a) first heating an as-cast specimen to 190 degrees C, (b) shearing there at gamma=0.085 s(-1) for about 5 min, and then (c) cooling slowly down to a predetermined temperature (130, 140, 150, 160, or 171 degrees C) in the nematic region. For each gamma chosen, after start-up of shear flow, we waited for a sufficiently long time until both the shear stress and first normal stress difference leveled off, giving rise to steady-state values of sigma and N-1. Emphasis was placed on investigating the effect of shear history on sigma and N-1 of PSHQ10 in the nematic region. For this, the following experiments were conducted : (a) a fresh specimen was sheared continuously by increasing the gamma stepwise, and (b) a presheared specimen was further sheared continuously by increasing the gamma stepwise. We have found that fresh specimens exhibited ’shear-thinning’ behavior over the entire range of gamma (0.008-0.27 s(-1)) tested, whereas the presheared specimens exhibited both zero-shear viscosities and shear-thinning behavior. When using fresh specimens, we found that N, was positive over the entire range of gamma (0.008-0.27 s(-1)) tested. However, when using presheared specimens we found that (a) at very low gamma, N-1 initially was negative and then became positive as shearing continued, and (b) at higher gamma, N-1 was positive over the entire duration of shearing.