http://en.wikipedia.org/wiki/Ottawa#cite_note-community_profile-28
From 2006 census:
<TABLE align=left><TBODY><TR bgColor=#cccccc><TH>Ethnic Origin</TH><TH>Population</TH><TH>Percent</TH></TR><TR><TD>
Canadian</TD><TD>227,490</TD><TD>28.4%</TD></TR><TR style="BACKGROUND: rgb(239,239,239); COLOR: black; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous"><TD>
English</TD><TD>194,845</TD><TD>24.3%</TD></TR><TR><TD>
Irish</TD><TD>180,525</TD><TD>22.5%</TD></TR><TR style="BACKGROUND: rgb(239,239,239); COLOR: black; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous"><TD>
French</TD><TD>172,165</TD><TD>21.5%</TD></TR><TR><TD>
Scottish</TD><TD>158,340</TD><TD>19.8%</TD></TR><TR style="BACKGROUND: rgb(239,239,239); COLOR: black; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous"><TD>
German</TD><TD>67,660</TD><TD>8.4%</TD></TR><TR><TD>
Italian</TD><TD>39,230</TD><TD>4.9%</TD></TR><TR style="BACKGROUND: rgb(239,239,239); COLOR: black; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous"><TD>
Chinese</TD><TD>34,435</TD><TD>4.3%</TD></TR><TR><TD>
Polish</TD><TD>25,685</TD><TD>3.2%</TD></TR><TR style="BACKGROUND: rgb(239,239,239); COLOR: black; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous"><TD>
Dutch</TD><TD>22,700</TD><TD>2.8%</TD></TR><TR><TD>
North American Indian</TD><TD>21,600</TD><TD>2.7%</TD></TR><TR style="BACKGROUND: rgb(239,239,239); COLOR: black; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous"><TD>
East Indian</TD><TD>20,525</TD><TD>2.6%</TD></TR><TR><TD>
Lebanese</TD><TD>17,500</TD><TD>2.1%</TD></TR><TR style="BACKGROUND: rgb(239,239,239); COLOR: black; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous"><TD>
African</TD><TD>16,000</TD><TD>2.0%</TD></TR></TBODY></TABLE>